סוגה
Sources
18
Electronic books
14
Periodicals
10
Handbooks, manuals, etc
6
Academic theses
4
Biography
4
Bibliography
2
Indexes
2
Popular works
2
Thèses et écrits académiques
2
Academic Dissertation
1
Catalogs
1
Classification
1
Codes
1
Collections
1
Early works to 1800
1
Guidebooks
1
Maps
1
Microform catalogs
1
Newspapers
1
Sermons
1
Texts
1
Treaties
1