Cyfyngwch eich canlyniadau yn ôl:
- Pob un
- Roberts, Evan, 1906-1991, 1 canlyniadau
- Salmon, H. Morrey (Harry Morrey), 1 canlyniadau
- Vaughan, H.R.H. 1893-1978, 1 canlyniadau
- Chater, A. O., 1 canlyniadau
- Chater, A. O. -- Correspondence., 1 canlyniadau
- Richards, Mary, 1885-1977, 1 canlyniadau
- Vaughan, Irene 1890-1993, 1 canlyniadau
- Evans, Evan Price, 1880-1959, 1 canlyniadau
- Ratcliffe, Derek, 1929- -- Correspondence., 1 canlyniadau
- Ratcliffe, Derek, 1929-, 1 canlyniadau
- Pob un
- Botany -- Wales, 3 canlyniadau
- Cwm Idwal (Wales), 1 canlyniadau
- Naturalists -- Wales, 1 canlyniadau
- Historic sites -- Wales, 1 canlyniadau
- Buzzards -- Wales, 1 canlyniadau
- Corvus corax -- Wales., 1 canlyniadau
- Outdoor education -- Great Britain, 1 canlyniadau
- Reclamation of land -- Great Britain, 1 canlyniadau
- Wales -- Historical geography, 1 canlyniadau
- Geology -- Wales, 1 canlyniadau