This completely revised edition of Scientific and Technical Information Sources is essentially a new book based on the framework of the 1977 edition and covering material published as recently as 1986. The first edition has been a library mainstay that has proved "invaluable to librarians, students, and scientists" (Choice). It was a major guide that went beyond the usual listings of guides to literature, dictionaries, encyclopedias, handbooks, directories, and other secondary sources to include substantial coverage of primary tools such as important series, periodicals, conference proceedings, and technical reports. It also included publications from professional societies, government documents, nonprint materials, and databases. The second edition has been extensively revised to include mostly current information sources published after 1980 with many published as recently as 1985 and 1986. Subjects have been deleted and added in sections throughout the book to reflect both the usage patterns and the timely evolution of various disciplines in science and technology. For example, references to computer technology now appear throughout the book's 23 chapters. Other extensive revisions include a complete revamping of the database section and the elimination of monographs since any selection of monographs is necessarily arbitrary. In addition to an author index, the book adds extensive title and subject indexes. Many of the entries have annotations that include critical as well as descriptive information, and review sources appear whenever possible.