Y cysgod ar y grisiau /
Halam, Ann.
Gruffudd, Elena.
Bright, Edmund.
University of Wales, Aberystwyth.Centre for Educational Studies.
Aberystwyth : Ganolfan Astudiaethau Addysg,
c2007.
Published as The Shadow on the Stairs in 2000 by Barrington Stoke Ltd., in Edinburgh.
Welsh language