Hydrogeology: A Short History, Part 2 - National Ground Water ...


Hydrogeology: A Short History, Part 2 - National Ground Water ...

Historical Note/

Hydrogeology: A Short History, Part 2

by C.W. Fetter Jr. 1


This paper, together with Part 1 (published in the September–October

2004 issue of Ground Water), provides a

short summary of the historical background of the science

of physical hydrogeology. Quantitative ground water

hydrology is the topic of Part 2. Here we find scientists and

engineers who used the scientific method to discover principles

of hydrogeology and apply them to problems of

water supply and contamination.

Beginnings of Quantitative

Ground Water Hydrology

It was in the 19th century that ground water hydrology

started to develop as a quantitative science. Henry Darcy

(1803–1858), a French civil engineer, was the first person

to determine the mathematical law that governs the flow of

ground water, which is now known as Darcy’s law. It was

based on experiments that he made on the flow of water

through sand filters. He published it in an appendix to his

report on a new water supply for the city of Dijon (Darcy

1856). Darcy determined that the flow of water through a

sand filter was a function of the head across the filter, the

cross sectional area of the filter, and the nature of the sand,

i.e., coarse or fine.

I approach now an account of the experiments that I carried

out at Dijon together with Engineer Charles Ritter, to determine

the laws of flow of water through sand . . . . Each experiment

consisted of establishing a specified pressure in the

upper chamber of the column by adjustment of the inflow

tap; then when it was established by means of two observations

that the flow had become essentially uniform, the outflow

from the filter during a certain time was noted, and the

mean outflow per minute was calculated from it. (Darcy


1 C.W. Fetter Jr. Associates, 11 Leamington Lane, Hilton Head

Island, SC 29928; (843) 842–2380; fax (843) 842–2386; cwfetter


Copyright © 2004 by the National Ground Water Association.

David Deming, History Editor

Just seven years later, A.J.E.J. Dupuit (1804–1866)

used Darcy’s law to derive an equation for the flow of water

to a well (Dupuit 1863). In 1870, Adolph Thiem, a German,

modified Dupuit’s formula so that one could calculate the

hydraulic properties of an aquifer by pumping a well and

observing the resulting decline in the water table in nearby

wells (Thiem 1887). Further advances in the mathematical

foundations of ground water flow were made in the 19th

century by Philip Forchheimer (1886), an Austrian, and

Charles Slichter (1899), an American.

The late 19th century also saw the development of a

more comprehensive understanding of the relationship of

ground water to the geological formations in which it

occurs. An American, T.C. Chamberlin—famous geologist,

professor at the University of Wisconsin, and an employee

of the U.S. Geological Survey (USGS)—published “The

Requisite and Qualifying Conditions of Artesian Wells”

(Chamberlin 1885). This was the first hydrogeologic report

published by the USGS. It provided a theoretical basis for

the scientific study of the occurrence of ground water and

thus prompted an explosion of activity in the evaluation of

ground water resources in the United States. Chamberlin

recognized that water occurred in both fractured and porous


There are two general methods by which water finds its way

through the strata: in the one—the rocks being close-textured—the

water passes through fissures formed by fracture,

or tubular channels formed by solution; in the other—the

rock being open-textured—the water seeps through the

pores, permeating the whole bed. (Chamberlin 1885)

Although Chamberlin’s work was groundbreaking, not

all of his concepts were correct. For example, it is not necessary

to have confining beds below an aquifer, and it is

possible to have a flowing well in the absence of structural


Chamberlin’s seminal work was followed by a paper

by Franklin H. King, another professor at the University of

Wisconsin and USGS employee, who wrote “Principles and

Conditions of the Movements of Ground Water” (King

1899). King introduced a number of important concepts in

this paper, including the movement of ground water due to

Vol. 42, No. 6—GROUND WATER—November–December 2004 (pages 949–953)


gravity. He showed the configuration of the water table

through the use of water level contour maps and indicated

the horizontal direction of ground water flow by the use of

arrows drawn at right angles to the contour lines. His original

figure is reproduced as Figure 1. This was possibly the

first ground water flow map.

His report also contains a cross section of a stream valley

with ground water flow lines originating beneath upland

areas and converging on the stream valley to discharge into

the stream. This is reproduced as Figure 2.

King was the first to observe that in humid areas, the

water table was a subdued reflection of the surface topography.

The contours of the ground water level show that this surface

presents the features of the hills and valleys approximately

conformable with the relief forms of the surface above, the

water being low where the surface of the ground is low, and

high where the surface of the ground is high. (King 1899)

Modern Era of Hydrogeology

Quantitative Hydrogeology

Scientific hydrogeology received a basic foundation in

the 19th century and came of age in the 20th. Further

progress was made in developing our understanding of the

mathematical basis of ground water movement. Slichter

wrote two more important papers, “The Motions of Underground

Water” (Slichter 1902) and “Field Measurements of

the Rate of Movement of Underground Water” (Slichter


C.V. Theis (1900–1987) of the USGS published two

papers of fundamental importance—“The Lowering of the

Piezometric Surface and the Rate and Discharge of a Well

Using Ground Water Storage” (Theis 1935) and “The Significance

and Nature of the Cone of Depression in Ground

Water Bodies” (Theis 1938). In his 1935 paper, Theis published

an equation to describe the decline of the piezometric

(potentiometric) surface in a fully confined aquifer due to the

withdrawal of water via a well. This paper forms the basis for

all other papers that quantify the flow of water to wells in

confined or semiconfined aquifers. In his 1938 paper, he

described the formation of a regional cone of depression and

its impact on the dynamic equilibrium of the aquifer.

In nature the hydraulic system in an aquifer is in balance; the

discharge being equal to the recharge and the water table or

other piezometric surface is more or less fixed in position.

Discharge by wells is a new discharge superimposed on the

previous system. Before a new equilibrium can be established,

water levels must fall throughout the aquifer to an

Figure 2. Cross section of aquifer showing flow lines (King 1899).


C.W. Fetter Jr. GROUND WATER 42, no. 6: 949–953

Figure 1. Ground water contour map (King 1899). Open circles

are wells used to determine water levels.

extent sufficient to reduce the natural discharge or increase

the recharge by an amount equal to the amount discharged by

the well. Until this new equilibrium is established water must

be withdrawn from storage in the aquifer and conversely the

new equilibrium cannot be established until an amount of

water is withdrawn from the well sufficient to depress the

piezometric surface enough to change the recharge or natural

discharge the proper amount. The depression of the piezometric

surface is called the cone of depression. (Theis 1938)

In 1940, M. King Hubbert (1903–1989) of the Shell Oil

Company published “The Theory of Ground Water

Motion” (Hubbert 1940). Hubbert placed a theoretical

foundation under the Darcy equation and introduced the

force potential, which combines the pressure and gravitational

potential. Through this work, he demonstrated that

Darcy’s law for ground water flow is analogous to Ohm’s

law for the flow of electricity. He also demonstrated that

flowing wells could be the result of the potential field even

in a homogeneous, isotropic aquifer.

Also in 1940, C.E. Jacob devised a graphical method of

interpreting aquifer test data for a pumping well in a fully

confined aquifer based on the Theis equation (Jacob 1940).

In 1955, M.S. Hantush and C.E. Jacob solved the problem

of quantifying nonsteady flow to a well in a leaky or semiconfined

aquifer (Hantush and Jacob 1955). Hantush later

published a number of papers describing flow in leaky

aquifers (Hantush 1956, 1960).

The fundamental basis for a mathematical description

of mass transport in porous media was postulated in papers

by De Josselin De Jong (1958) and Ogata and Banks (1961)

in which the concept of longitudinal and transverse dispersion

and diffusion were presented.

The papers previously mentioned firmly established

the fundamentals of the modern knowledge of quantitative

ground water movement and they led to an explosion of

papers published starting in the 1960s.

Ground Water Exploration

The first part of the 20th century also saw a rapid

expansion of the exploration for ground water supplies,

especially by the USGS. Starting about 1900, hydrogeologists

from the USGS fanned out across the United States.

Early photos show these pioneering geologists riding horses

and buggies across the prairies and deserts of the western

United States. Some examples of their early work includes

studies of N.H. Darton in South Dakota and Wyoming

(1901, 1905), M.L. Fuller in the eastern United States

(1904), W. Lindgren in Hawaii (1903), W.T. Lee in Arizona

(1904, 1905), W.C. Mendenhall in California (1905),

and C.E. Siebenthal in Colorado (1910).

O.E. Meinzer, who was chief of the Ground Water

Division of the USGS from 1912 to 1946, synthesized the

results of numerous regional studies of ground water to prepare

Water Supply Paper 429, “The Occurrence of Ground

Water in the United States with a Discussion of Principles”

(Meinzer 1923). In this, he organized and integrated knowledge

from various regional reports into a coherent whole, as

well as setting important principles for the occurrence of

ground water. He also developed the ground water inventory

methods that can be used to determine the amount of

water passing through a ground water basin.

The rocks that form the surface of the earth are in few places,

if anywhere, solid throughout. They contain numerous open

spaces, called voids or interstices, and these spaces are the

receptacles that hold the water that is found beneath the surface

of the land and is recovered in part through springs and

wells. There are many kinds of rocks, and they differ greatly

in the number, size, shape and arrangement of their interstices

and hence in their properties as containers of water.

The occurrence of water in the rocks of any region is therefore

determined by the character, distribution and structure of

the rocks it contains—that is by the geology of the region.

(Meinzer 1923,)

Ground Water Contamination

Knowledge about ground water contamination developed

approximately parallel to knowledge about the occurrence

and movement of ground water. One reason for this is

the fact that it was not until the work of Louis Pasteur that

we knew that disease could be caused by microorganisms.

As late as the Civil War in the United States (1861–1865),

the correlation between contaminated water and disease

was not widely known. More soldiers died of disease than

bullets and sabers in the Civil War.

In 1849, John Snow, a London physician, wrote a

paper that claimed that cholera was spread by a “poison”

from the excreta and vomit of cholera victims and that it

could potentially be spread by contaminated drinking water

(Snow 1849). A few years later, he was able to show that

the London cholera epidemic of 1854 was spread by ground

water taken from a certain public well on Broad Street. He

stopped the epidemic by removing the pump handle.

Industrial processes of the 19th century, especially the

manufacture of gas, were known to cause contamination of

wells. In 1856, a manufactured gas plant was built in

Pottstown, Pennsylvania. A disposal well was constructed

in sandy soil to receive the ammonia water from the gas

washer. Within months, the water well supplying an adjacent

hotel became “wholly unfit for use” (Pottstown Gas

Company v. Murphy 1861).

In 1873, Austin Flint, an American doctor, wrote an

article in which he demonstrated that typhoid fever was

contracted by drinking contaminated ground water (Flint

1873). A year later, Edward Orton, the president of what is

now Ohio State University, wrote a remarkable paper that

noted that ground water not only flowed from place to

place, but that as it flowed, it could dissolve substances

from the soil and, if ground water flowed through human

waste, it could pick up disease (Orton 1874). Industrial contamination

was also known to be a potential ground water

contaminant in the last part of the 19th century, as wastes

from gas works were known to have polluted nearby wells

(Sheldon 1897).

During the first decade of the 20th century, the USGS

also published several papers on ground water contamination

problems, including sewage disposal problems in limestone

bedrock (McCallie 1905), disposal of oily wastes

from oil wells (Bowman 1905), contamination of wells in

sandy deposits (Fuller 1910), and another paper on sewage

disposal in limestone aquifers (Matson 1910).

One of the major industries of the first part of the 20th

century that caused pollution problems in water was the

manufacture of gas from coal. One reason for this was that

the wastes contained phenol, which has an objectionable

taste when dissolved in water.

In 1908, a brewery in New Jersey sued the owners of

an adjacent manufactured gas plant for contaminating their

well with tarry waste, which had been allowed to seep into

the ground (Ballentine and Sons v. Public Service Corporation

of New Jersey 1908, 1914).

Ground water which had been contaminated with wastes

from manufactured gas plants were known to be capable of

traveling considerable distance through the ground.

Another bad effect of gas house wastes which has here and

there given rise to more or less serious trouble is the pollution

of the soil, which in turn gives rise to gassy tastes in water

wells and gassy odors in cellars. A striking example of this

occurred in Joliet, where one of the public water supply wells

was affected by a gassy taste that could be explained on no

other basis than contamination from a gas plant nearby. The

writer had occasion some years ago to observe a similar

C.W. Fetter Jr. GROUND WATER 42, no. 6: 949–953


instance of the long travel of gassy wastes at the town of

Carthage, in southern Ohio. Here the pollution was occasioned

by coal tar wastes used at a tar paper factory. These

wastes were permitted to flow into a pit at least 2000 feet

from the affected wells. (Hanson 1916)

During the 1920s and 1930s, experimental fieldwork

was done on the travel of various contaminants through

aquifers. Stiles and Crohurst (1923, 1927) studied the movement

of bacteria through aquifers. A.F. Dappert (1932)

studied the movement of a plume of contaminated ground

water by tracing the amount of dissolved chloride for a distance

of 1500 feet and C.K. Calvert (1932) found that

organic wastes dissolved in ground water traveled 500 feet

in eight months. A paper written by Harmon (1941) noted

that there were many types of wastes that should be kept out

of ground water to avoid pollution and gave a few examples

including “greasy wastes from tanneries, packing plants,

woolen mills; oily wastes from oil wells and refineries;

soapy wastes from laundries; acid wastes from chemical

works and oil refineries; saline wastes from oil wells ....”

In the United States, industrial production was greatly

increased during World War II. At that time, environmental

protection was not a priority. Problems of ground water

contamination were discovered soon after the war started.

Two cases of ground water contamination by dissolved

heavy metals are noteworthy. Both situations occurred in

Long Island, New York, where the water table is shallow,

the aquifer is permeable, and waste water containing cadmium

and chromium from metal part plating were put into

seepage ponds. Davids and Lieber (1951) described

chromium contamination and Lieber and Welsch (1954)

addressed cadmium contamination. These papers demonstrated

that contaminated ground water could travel many

hundreds of feet through sand aquifers.


The general nature of the hydrologic cycle and the circulation

of ground water was a topic that was typically discussed

in textbooks for general courses in geology and

physical geography written in the first part of the 20th century.

A few examples are listed here.

● Elements of Geology by Joseph Le Conte, revised by

Herman LeRoy Fairchild, 5th edition, 1915, New

York: D. Appleton.

● A Textbook of Geology, Part 1. Physical Geology by

Chester R. Longwell, Adolph Knopf, and Richard F.

Flint, 2nd edition, 1939, New York: John Wiley &


● Lessons in Physical Geography by Charles Redway

Dryer, 1916, New York: American Book.

● The Elements of Geography by Rollin D. Salisbury,

Harlan H. Barrows, and Walter S. Tower, 1913, New

York: Henry Holt.

More specialized textbooks also had sections on

ground water. William P. Mason of Renesselaer Polytechnic

Institute published a book, Water Supply, in 1896

(Mason 1896). In this book, he has two chapters devoted to

ground water. In them, he discusses the source, occurrence,

and movement of ground water, and how to obtain ground


C.W. Fetter Jr. GROUND WATER 42, no. 6: 949–953

water via wells. He also discussed in some depth how

ground water becomes contaminated by sanitary waste and

how this can be avoided.

In 1937, C.F. Tolman of Leland Stanford Junior College

(now Stanford University) published an entire book

dedicated to only one subject—Ground Water. Tolman’s

book on ground water was so complete and up to date in

1937 that another general textbook on ground water,

Ground Water Hydrology by David K. Todd, also of Stanford

University, was not published until 1959.

Since 1959, a large number of textbooks on many

aspects of hydrogeology have been published in the United

States. However, their contents are in many ways based on

work done by the pioneering hydrogeologists and engineers

introduced in this brief paper.

Introduction to Hydrogeology by David Deming

(2002) contains short biographies of many of the pioneering

hydrogeologists mentioned in this paper.


I would like to thank Dr. Stan Davis of the University

of Arizona and Dr. David Deming of the University of

Oklahoma for their helpful comments on this manuscript.


Ballentine and Sons v. Public Service Corporation of New Jersey,

91 A 167 (1908, 1914).

Bowman, I. 1905. Disposal of oil well wastes at Marion, Indiana.

U. S. Geological Survey Water Supply Paper 113.

Calvert, C.K. 1932. Contamination of ground water by impounded

garbage waste. Journal AWWA 24, 266–276.

Chamberlin, T.C. 1885. The requisite and qualifying conditions of

artesian wells. U.S. Geological Survey 5th Annual Report.

Dappert, A.F. 1932. Tracing the travel and changes in composition

of underground pollution. Water Works and Sewerage 79,

no. 8: 265–274.

Darcy, H. 1856. Les fontaines publisues de la ville de Dijon. Paris:

Victor Dalmont.

Darton, N.H. 1901. Preliminary description of the geology and

water resources of the southern half of the Black Hills and

adjoining regions of South Dakota and Wyoming. U.S. Geological

Survey 21st Annual Report, Part 4.

Darton, N.H. 1905. Preliminary report on the geology and underground

water resources of the central Great Plains. U.S. Geological

Survey Professional Paper 32.

Davids, H.W., and M. Lieber. 1951. Underground contamination

by chromium waste. Water and Sewage Works 98, no. 12:


De Josselin De Jong, G. 1958. Longitudinal and transverse diffusion

in granular deposits. Transactions, American Geophysical

Union 39, no 1: 67–74.

Deming, D. 2002. Introduction to Hydrogeology. New York:


Dupuit, A.J.E.J. 1863. Etudes theoriques et practiques sur le mouvement

de eaux das les canaux decouverts et a travers les terrains

permeables, 2nd edition. Paris: Dunod.

Flint, A. 1873. Relation of water to the propagation of fever. Public

Health 1, 164–172.

Forchheimer, P. 1886. Uber die Ergebigkeit von Brunnen Anlagen

und Sickerschlitzen. Zeitschrift des Architekten und Ingenieur

Vereins zu Hannover 32, 539–564.

Fuller, M.L. 1904. Contributions to the geology of the eastern

United States, 1903. U.S. Geological Survey Water Supply

Paper 102.

Fuller, M.L. 1910. Protection of shallow wells in sandy deposits.

U.S. Geological Survey Water Supply Paper 258.

Hanson, P. 1916. Disposal of gas house wastes. Illinois Gas Association

Proceedings 12, 124–135.

Hantush, M.S. 1956. Analysis of data from pumping tests in leaky

aquifers. Transactions, American Geophysical Union 37, no.

6: 702–714.

Hantush, M.S. 1960. Modification of the theory of leaky aquifers.

Journal of Geophysical Research 65, no. 11: 3713–3725.

Hantush, M.S., and C.E. Jacob. 1955. Nonsteady radial flow in an

infinite leaky aquifer. Transactions, American Geophysical

Union 36, no. 1: 95–100.

Harmon, B. 1941. Contamination of ground-water resources. Civil

Engineering 11, no. 6: 345–347.

Hubbert, M.K. 1940. The theory of ground water motion. Journal

of Geology 48, no. 8: 785–944.

Jacob, C.E. 1940. The flow of water in an elastic artesian aquifer.

Transactions, American Geophysical Union 21, 574–586.

King, F.H. 1899. Principles and conditions of the movements of

ground water. U.S. Geological Survey 19th Annual Report,

Part 2.

Lee, W.T. 1904. The underground waters of the Gila Valley, Arizona.

U.S. Geological Survey Water Supply Paper 104.

Lee, W.T. 1905. The underground waters of Salt River Valley,

Arizona. U.S. Geological Survey Water Supply Paper 136.

Lieber, M., and W.F. Welsch. 1954. Contamination of ground

water by cadmium. Journal AWWA 46, 541–547.

Lindgren, W. 1903. The water resources of Molokai, Hawaiian

Islands. U.S. Geological Survey Water Supply Paper 77.

Mason, W.P. 1896. Water Supply (Considered Primarily from a

Sanitary Standpoint). New York: John Wiley & Sons.

Matson, G.C. 1910. Pollution of underground waters in limestone.

U.S. Geological Survey Water Supply Paper 258.

McCallie, S.W. 1905. Experiment relating to problems of well

contamination in Quitman, Georgia. U.S. Geological Survey

Water Supply Paper 110.

Meinzer, O.E. 1923. The occurrence of ground water in the United

States with a discussion of principles. U.S. Geological Survey

Water Supply Paper 489.

Mendenhall, W.C. 1905. Development of underground waters in

the eastern coastal-plain region of southern California. U.S.

Geological Survey Water Supply Paper 137.

Ogata, A., and R.B. Banks. 1961. A solution of the differential

equation of longitudinal dispersion in porous media. U.S.

Geological Survey Professional Paper 411-A.

Statement required by the act of August 12, 1970, Section 3685,

Title 39, United States Code) showing the ownership, management,

and circulation of:

Ground Water, publication number 0017-467X, published bi-monthly

at 601 Dempsey Rd., Westerville, OH 43081. Number of issues published

annually: 6. Annual subscription price: $280 domestic; $295 international.

The general business offices of the publisher are located at 601 Dempsey

Rd., Westerville, OH 43081-8978.

The names and addresses of the publisher, editor, and managing editor

are: publisher, Thad Plumley, 601 Dempsey Rd., Westerville, OH 43081-

8978; editor, Mary P. Anderson, 1215 W. Dayton St., Madison, WI 53706;

managing editor, Pat Levak, 601 Dempsey Rd., Westerville, OH 43081-8978.

The owner is National Ground Water Association, 601 Dempsey Rd., Westerville,

OH 43081-8978. The names and addresses of stockholders owning

or holding 1 percent or more of the total amount of stock are: None.

Known bondholders, mortgagees, and other security holders owning or holding

1 percent or more of total amount of bonds, mortgages, or other securities

are: None.

The average number of copies each issue during the preceding 12

months are:

a. Total number of copies printed:

Net press run: 11,580

b. Paid and/or requested circulation:

1. Mail subscriptions: 10,901

2. Sales through dealers and carriers, street vendors,

and counter sales: 0

c. Total paid and/or requested circulation: 10,901

Orton, E. 1874. Certain relations of geology to the water supplies

of the county. Public Health 2, 292–305.

Pottstown Gas Company v. Murphy, 39 PA 257 (1861).

Siebenthal, C.E. 1910. Geology and water resources of the San

Luis Valley, Colorado. U.S. Geological Survey Water Supply

Paper 240.

Sheldon, F.H. 1897. The nuisance question in gas works. Proceedings

of the Northeastern Association of Gas Engineers,


Slichter, C.S. 1899. Theoretical investigation of the motion of

ground water. U.S. Geological Survey 19th Annual Report,

Part 2.

Slichter, C.S. 1902. The motions of underground waters. U.S.

Geological Survey Water Supply Paper 67.

Slichter, C.S. 1905. Field measurements of the rate of movement

of underground waters. U.S. Geological Survey Water Supply

Paper 140.

Snow, J. 1849. On the mode of communication of cholera. London

Medical Gazette XLIV, 730–732.

Stiles, C.W., and H.R. Crohurst. 1923. Principles underlying the

movement of E. coli in ground water with the resulting pollution

of wells. Public Health Report 38, 1350–1350.

Stiles, C.W., and H.R. Crohurst. 1927. Experimental bacterial and

chemical pollution of wells via ground water with a report on

the geology and ground water hydrology of the experimental

area at Fort Casell, North Carolina. U.S. Public Health Service

Hygiene Laboratory Bulletin 147, 88–90.

Theis, C.V. 1935. The lowering of the piezometric surface and the

rate and discharge of a well using ground water storage.

Transactions of the American Geophysical Union 16,


Theis, C.V. 1938. The significance and nature of the cone of

depression in ground water bodies. Economic Geology 38,


Thiem, A. 1887. Verfahress für Naturlicher Grundwassergeschwindegkiten.

Polyt. Notizblatt 42, 229.

Todd, D.K. 1959. Ground-Water Hydrology. New York: John

Wiley & Sons.

Tolman, C.F. 1937. Ground Water. New York: McGraw-Hill.

d. Free distribution by mail (samples, complimentary and

other free copies): 0

e. Free distribution outside the mail: 0

f. Total free distribution: 0

g. Total distribution: 10,901

h. Copies not distributed: 679

i. Total: 11,580

j. Percent paid and/or requested circulation: 100%

The actual number of copies of single issue published nearest to filing

date are:

a. Total number of copies printed:

Net press run: 11,330

b. Paid and/or requested circulation:

1. Mail subscriptions: 10,759

2. Sales through dealers and carriers, street vendors,

and counter sales: 0

c. Total paid and/or requested circulation: 10,759

d. Free distribution by mail (samples, complimentary and

other free copies): 0

e. Free distribution outside the mail: 0

f. Total free distribution: 0

g.. Total distribution: 10,759

h. Copies not distributed: 571

i. Total: 11,330

j. Percent paid and/or requested circulation: 100%

I certify that the statements made by me above are correct and complete.

Thad Plumley, Publisher

C.W. Fetter Jr. GROUND WATER 42, no. 6: 949–953


More magazines by this user
Similar magazines