Genre
- Electronic books 1,266 canlyniadau
- Congresses 74 canlyniadau
- Textbooks 52 canlyniadau
- Handbooks, manuals, etc 40 canlyniadau
- Laboratory manuals 12 canlyniadau
- Biography 10 canlyniadau
- Dictionaries 10 canlyniadau
- Examinations, questions, etc 10 canlyniadau
- Popular works 10 canlyniadau
- Problems, exercises, etc 10 canlyniadau
- Formulae, receipts, prescriptions 4 canlyniadau
- Identification 4 canlyniadau
- Study guides 4 canlyniadau
- Tables 4 canlyniadau
- Encyclopedias 2 canlyniadau
- Experiments 2 canlyniadau
- General 2 canlyniadau
- Humor 2 canlyniadau
- Interviews 2 canlyniadau
- Juvenile literature 2 canlyniadau
- Materials 2 canlyniadau
- Methods 2 canlyniadau
- Nomenclature 2 canlyniadau
- Observations 2 canlyniadau
- Outlines, syllabi, etc 2 canlyniadau
- Patents 2 canlyniadau
- Periodicals 2 canlyniadau