Rhif cytundeb Cyngor Cefn Gwlad Cymru = C.C.W. contract no.: FC 73-01-232.
The status and distribution of the freshwater pearl mussel (Margaritifera margaritifera (L.,1758)) in Wales : 1998/99 survey of the Afon Tâf and Afon Tywi by Ian J. Killeen. Published by Countryside Council for Wales in 1999. Publication and catalogue information, links to buy online and reader comments.