principles and applications of microearthquake networks

14 1. Introduction
indicated the language in which it is written. We have cited many USGS
Open-File Reports, which are on file at the libraries of the U.S. Geological
Survey in Reston, Virginia; Denver, Colorado; and Menlo Park, California.
We hope that this work will provide some guidance for scientists beginning
this field of research and will serve as a general reference on microearthquake
studies. In an attempt to make this book more useful to
readers, we have prepared a Glossary, an Author Index, and a Subject
Index. If a certain term is not familiar to the reader, the following steps
are recommended: (1) consult the Subject Index and refer to the pages
where the term in question may be defined or discussed, (2) consult the
Glossary, or (3) consult the standard references given in the Glossary.
The Author Index lists all the names that appear explicitly in the text. A
paper with three or more authors is referred to in the text by the name of
the first author followed by et al. Because the names of the other authors
in this case do not appear explicitly, they are not indexed. However, all
authors in the References section are included in the Author Index.