Contents 1
21．What Information Is after Harlan Cleveland 1
22．Post-Industrial Society and the Growth of Information:The Impact on Libraries by Rollin Marquis 12
23．Information Science—an Introduction by Charles H．Davis and James E．Rush 23
24．Information Transfer Cycle by F．W．Lancaster 32
25．Information Sources after William A．Katz 41
26．Bibliographies after William A．Katz 50
27．Indexes aftel Jean Key Gates 59
28．Encyclopedias after Jean Key Gates 70
29．Dictionaries by Jean Key Gates 82
30．Biographical Sources after Jean Key Gates 94
31．Ready-Reference Sources by William A．Katz 104
32．Geographical Sources after Jean Key Gates 115
33．Databases and Online Bibliographic Database Searching after Ching-chih Chen 126
34．Networks after William A．Katz 140
35．Information Retrieval and Boolean Logic by Claire Guinchat and Michel Menou 152
36．Online Catalogs after Joseph R.Matthews 164
37．Indexing and Vocabulary Control by Charles 177
H．Davis and James E．Rush 177
38．Abstracts and Abstracting by Charles H．Davis and James E．Rush 193
39．Research and Scientific Method by Charles H．Busha 206
40．Communication and Information by Claire Guinchat and Michel Menou 218
Key to Exercises Ⅱ and Ⅲ 234