Genre
Sources
31
Periodicals
14
Newspapers
10
Congresses
9
Bibliography
3
Biography
3
Early works to 1800
3
Handbooks, manuals, etc
3
Case studies
2
Controversial literature
2
Mikroform
2
Pictorial works
2
Statistics
2
Academic theses
1
Catalogs
1
Classification
1
Digests
1
Early works to 1900
1
Examinations, questions, etc
1
Fiction
1
Juvenile fiction
1
Juvenile literature
1
Maps
1
Terminology
1
Translations into German
1