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Handbooks, manuals, etc
6
Congresses
5
Examinations, questions, etc
4
Periodicals
4
Study guides
4
Case studies
3
Examination Questions
3
Outlines
3
Congresses.#
2
programmed instruction
2
Atlases
1
Biography
1
Directories
1
Directory
1
Encyclopedias
1
Juvenile literature
1
Popular Works
1
Popular works
1
Problems and Exercises
1
Problems, exercises, etc
1
Textbooks
1
handbooks
1