Genre
Periodicals
143
Serial publications
49
Conference papers and proceedings
15
Congresses
9
Statistics
9
Directories
7
Catalogs
6
Bibliographies
5
Tables (Data)
4
Abstracts
3
Electronic journals
3
Maps
3
Yearbooks
3
Handbooks and manuals
2
Annual reports
1
Encyclopedias
1
Ephemerides
1
Examinations
1
Guidebooks
1
Nomenclature
1
Observations
1
Programmed instructional materials
1
Reference works
1
Study guides
1
Technical reports
1