Gerau /
Ollerenshaw, Chris.
Triggs, Pat.
Millard, Peter,1960-
Jones, Berwyn Prys.
Penryn : Ivan Corbett,
1994.
Arg. Saesneg gwreiddiol = Original English ed: London: A & C Black, 1991
Addasiad Cymraeg = Welsh adaptation: Berwyn Prys Jones