Casgliadau Arlein
Amgueddfa Cymru
Chwilio Uwch
Applicability of Short-Period Delay Detonators in Safety-Lamp Mines (report)
Safety in Mines Research Establishment Report No. 45. 46 pages, stapled.
Nid yw sylwadau ar gael ar hyn o bryd. Ymddiheuriadau am yr anghyfleustra.