4. References
Bulman, C. R. (2001). Conservation biology of the marsh fritillary butterfly F.uphxdrxas aurinia.
Ph.D.. University of Leeds. Fowles. A. P. (1983). Report of the Marsh Fritillary Survey of Ceredigion. Unpublished report.
Countryside Council for Wales. Bangor. Fowles, A. P. (1984). Population Studies of the Marsh Fritillary Colony at Rhos Llawrcwrt NNR.
Dyfed. Unpublished report. Countryside Council for Wales. Bangor. Fowles. A. P. (1991). Aspects of Monitoring at Rhos Llawrcwrt NNR. Unpublished report.
Countryside Council for Wales. Bangor. Fowles. A. P. (2004). Conservation objective for marsh fritillaries on marshy grassland.
Unpublished report. Countryside Council for Wales. Bangor. Fowles. A. P. (2005). Habitat quality mapping for marsh fritillary populations. CCW Staff
Science Report No. 05/5/1. Unpublished report. Countryside Council for Wales, Bangor. Pollard. E. (1977). A method for assessing changes in the abundance of butterflies. Biology and
Conservation. 12. 115-134. Robertson. J. and Wheeler. D. (2002). Reserve focus: Rhos Uawrcwrt NNR. Ceredigion. British
Wildlife. 13(3). 171-176. Thomas. J. and Lewinglon. R. (1991). The Butterflies of Britain and Ireland. Dorhng Kindersley. London.
Wilkinson. K. (2005). Rhos Uawrcwrt SAC/NNR marsh fritillary SAC monitoring 2005.
Unpublished report. Countryside Council for Wales. Bangor. 
Woolley. D. (1991-2006). Rhos Llawrcwrt NNR marsh fritillary studies. Unpublished report. Countryside Council for Wales. Bangor.