(1981). A glimpse of the past: A tourist's guide to industrial trails, slate quarries, mines, mills. Cardiff: Wales Tourist Board.
Lua i Stíl Chicago (17ú heag.)A Glimpse of the Past: A Tourist's Guide to Industrial Trails, Slate Quarries, Mines, Mills. Cardiff: Wales Tourist Board, 1981.
Lua MLA (8ú heag.)A Glimpse of the Past: A Tourist's Guide to Industrial Trails, Slate Quarries, Mines, Mills. Cardiff: Wales Tourist Board, 1981.
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