Genre
Sound recordings
4,315
Statistics
2,504
Technical reports
1,515
Handbooks and manuals
1,415
Conference papers and proceedings
975
Treaties
866
Maps
270
Bibliographies
232
Case studies
211
Databases
167
Directories
132
Biographies
121
Congresses
116
Census data
101
Catalogs
88
Classification
87
Dictionaries
77
Examinations
73
Guidebooks
64
Trivia and miscellanea
59
Legislative hearings
45
Periodicals
38
Encyclopedias
34
Study guides
34
Tables (Data)
33
Blank forms
32
Personal correspondence
29
Vital statistics
28
Academic theses
27
Registers (Lists)
27
Festschriften
24
Records (Documents)
22
Graphs
20
Indexes
20
Literature
20
Laboratory manuals
19
Legislative materials
19
Geographic information systems
18
Identification
18
Observations
18
Photographs
18
Illustrated works
16
Software
16
Atlases
15
Calendars
15
Longitudinal studies
15
Chronologies
14
Exhibition catalogs
14
Interviews
14
Popular works
14
more ...