Dolgarrog : description of 1:25 000 sheet SH76 /
Howells, M. F.(Malcolm Fletcher)
Institute of Geological Sciences (Great Britain)
London : H.M.S.O.,
1981.
Col. maps on inside covers
'Institute of Geological Sciences, Natural Environment Research Council'
2 copies: 1 in a plastic wallet with map.
Bibliography: p76-79. - Includes index
Geology