Genre
- Congresses 53 canlyniadau
- Periodicals 18 canlyniadau
- Handbooks, manuals, etc 9 canlyniadau
- Statistics 7 canlyniadau
- Case studies 4 canlyniadau
- Directories 4 canlyniadau
- Juvenile literature 4 canlyniadau
- Bibliography 2 canlyniadau
- Databases 2 canlyniadau
- Specifications 2 canlyniadau
- Catalogs 1 canlyniadau
- Fiction 1 canlyniadau
- Pictorial works 1 canlyniadau
- Readers 1 canlyniadau
- Safety regulations 1 canlyniadau