1953 Vintage OS Ordnance Survey 1:25000 First Series Map SH 63 Talsarnau.
The area covered ranges from Penrhyndeudraeth and the Dwyryd estuary to Talsarnau, but of most interest is the detailed topography of the Rhinog mountains north of Cwm Bychan. Final publication was in 1953 with minor corrections in 1961.