Genre
- Congresses 5,049 canlyniadau
- Periodicals 738 canlyniadau
- Biography 520 canlyniadau
- Juvenile literature 517 canlyniadau
- Problems, exercises, etc 300 canlyniadau
- Textbooks 260 canlyniadau
- Handbooks, manuals, etc 233 canlyniadau
- Popular works 232 canlyniadau
- Classification 197 canlyniadau
- Laboratory manuals 170 canlyniadau
- Identification 157 canlyniadau
- Dictionaries 143 canlyniadau
- Early works to 1800 143 canlyniadau
- Pictorial works 130 canlyniadau
- Encyclopedias 100 canlyniadau
- Tables 100 canlyniadau
- Miscellanea 95 canlyniadau
- Atlases 82 canlyniadau
- Case studies 51 canlyniadau
- Nomenclature 47 canlyniadau
- Maps 44 canlyniadau
- Observations 36 canlyniadau
- Anecdotes 35 canlyniadau
- Bibliography 34 canlyniadau
- Databases 31 canlyniadau
- Catalogs 27 canlyniadau
- Correspondence 27 canlyniadau
- Observers' manuals 24 canlyniadau
- Folklore 21 canlyniadau
- Charts, diagrams, etc 19 canlyniadau
- Terminology 19 canlyniadau
- Outlines, syllabi, etc 17 canlyniadau
- Abstracts 15 canlyniadau
- Study guides 15 canlyniadau
- Examinations, questions, etc 14 canlyniadau
- History 12 canlyniadau
- Interviews 12 canlyniadau
- Photographs from space 12 canlyniadau
- Sources 12 canlyniadau
- Directories 10 canlyniadau
- Guidebooks 10 canlyniadau
- Pre-Linnean works 10 canlyniadau
- Catalogs and collections 9 canlyniadau
- Humor 9 canlyniadau
- Juvenile fiction 9 canlyniadau
- Quotations, maxims, etc 9 canlyniadau
- Nomenclature (Popular) 8 canlyniadau
- Outdoor books 8 canlyniadau
- Indexes 7 canlyniadau
- Amateurs' manuals 6 canlyniadau rhagor...