Cyfyngwch eich canlyniadau yn ôl:
- Pob un
- Pennant, Thomas, 1726-1798, 1 canlyniadau
- Peate, Iorwerth Cyfeiliog, 1901-1982, 1 canlyniadau
- Owen, Bob, 1885-1962, 1 canlyniadau
- Peate, Iorwerth Cyfeiliog, 1901-1982 -- Correspondence, 1 canlyniadau
- Ingram, G.C.S. (Geoffrey Cheselden S.), 1881-1971 -- Correspondence, 1 canlyniadau
- North Wales Naturalists' Trust, 1 canlyniadau
- Brook, Arthur, 1886-1957 -- Correspondence., 1 canlyniadau
- Owen, Bob, 1885-1962 -- Correspondence, 1 canlyniadau
- Owen, J.H., d. 1959 -- Correspondence, 1 canlyniadau
- Ingram, G.C.S. (Geoffrey Cheselden S.), 1881-1971,, 1 canlyniadau
- Pob un
- Pine marten, 2 canlyniadau
- Landscape -- Wales -- Snowdonia, 1 canlyniadau
- European polecat, 1 canlyniadau
- Natural areas -- Wales -- Snowdonia., 1 canlyniadau
- Nature conservation -- Wales -- Snowdonia, 1 canlyniadau
- Snowdonia (Wales) -- Historical geography, 1 canlyniadau
- Badgers, 1 canlyniadau
- Bats, 1 canlyniadau
- Dormice, 1 canlyniadau
- Hares, 1 canlyniadau
