Genre
- Congresses 498 bohtosa
- Periodicals 255 bohtosa
- Biography 144 bohtosa
- Problems, exercises, etc 65 bohtosa
- Popular works 46 bohtosa
- Handbooks, manuals, etc 42 bohtosa
- Textbooks 40 bohtosa
- Juvenile literature 37 bohtosa
- Observations 36 bohtosa
- Tables 25 bohtosa
- Dictionaries 24 bohtosa
- Laboratory manuals 20 bohtosa
- Maps 14 bohtosa
- Encyclopedias 12 bohtosa
- Early works to 1800 10 bohtosa
- Miscellanea 9 bohtosa
- Atlases 6 bohtosa
- Bibliography 6 bohtosa
- Early works to 1850 5 bohtosa
- Examinations, questions, etc 5 bohtosa
- Anecdotes 4 bohtosa
- Case studies 4 bohtosa
- Charts, diagrams, etc 4 bohtosa
- History 4 bohtosa
- Observers' manuals 4 bohtosa
- Pictorial works 4 bohtosa
- Statistics 4 bohtosa
- Abstracts 3 bohtosa
- Indexes 3 bohtosa
- Correspondence 2 bohtosa
- Diaries 2 bohtosa
- Folklore 2 bohtosa
- Rocket observations 2 bohtosa
- Study guides 2 bohtosa
- Terminology 2 bohtosa
- Amateurs' manuals 1 bohtosa
- Bathymetric maps 1 bohtosa
- Catalogs 1 bohtosa
- Comic books, strips, etc 1 bohtosa
- Fiction 1 bohtosa
- Formulae 1 bohtosa
- Genealogy 1 bohtosa
- Guidebooks 1 bohtosa
- Humor 1 bohtosa
- Interviews 1 bohtosa
- Observers manuals 1 bohtosa
- Remote-sensing images 1 bohtosa