Shilland, E; Irvine, L; Malcolm, IA; (2010) UK Acid Waters Monitoring Network (UKAWMN) - Contract 22 01 249. Llyn Cwm Mynach, Afon Hafren and Afon Gwy - Annual Summary Progress Report. April 2009 - March 2010. (ECRC Research Report ). ECRC (Environmental Change Research Centre, University College London)