Welsh slatemen of America : published to mark the visit to Llechwedd of the National Welsh American Foundation 4 July 1993 /
Jones, Ivor Wynne.
National Welsh-American Foundation.
Blaenau Ffestiniog : Llechwedd Slate Caverns,
1993.
At head of cover title: Llechwedd Slate Caverns.
Llechwedd Slate Mines
Slate industry
Slate industry