Genre
Electronic books
188
Case studies
20
Biography
15
Documentary films
11
Congresses
10
DVD-Video discs
8
Electronic book
8
Documentary television programs
6
Nonfiction films
6
Sources
5
Video recordings for the hearing impaired
5
Environmental films
3
Feature films
3
Nonfiction television programs
3
Periodicals
3
Atlases
2
Bibliography
2
Biographies
2
Classification
2
Educational films
2
Essays
2
Maps
2
Pictorial works
2
Video recordings for people with visual disabilities
2
Abstracts
1
Biographical television programs
1
Catalogs
1
Designs and plans
1
Environmental television programs
1
Exhibitions
1
Geographic information systems
1
Historical television programs
1
History
1
Illustrated works
1
Juvenile literature
1
Literary collections
1
Nature films
1
Nature television programs
1
Panel discussions
1
Science television programs
1
Travel writing
1
Videocassettes
1