Casgliadau Arlein
Amgueddfa Cymru
Chwilio Uwch
Spoil Heaps and Lagoons (handbook)
National Coal Board Technical Handbook. Second draft, September 1970. 234 pages with blue covers and plastic binding.
Nid yw sylwadau ar gael ar hyn o bryd. Ymddiheuriadau am yr anghyfleustra.