Brereton, Tom M.; Warren, Martin S.; Roy, David B.; Stewart, Katherine (20 July 2007). "The changing status of the Chalkhill Blue butterfly Polyommatus coridon in the UK: the impacts of conservation policies and environmental factors". Journal of Insect Conservation. 12 (6): 629–638. doi:10.1007/s10841-007-9099-0. ISSN1366-638X. S2CID22067588.
Brereton, Tom M.; Warren, Martin S.; Roy, David B.; Stewart, Katherine (20 July 2007). "The changing status of the Chalkhill Blue butterfly Polyommatus coridon in the UK: the impacts of conservation policies and environmental factors". Journal of Insect Conservation. 12 (6): 629–638. doi:10.1007/s10841-007-9099-0. ISSN1366-638X. S2CID22067588.
Brereton, Tom M.; Warren, Martin S.; Roy, David B.; Stewart, Katherine (20 July 2007). "The changing status of the Chalkhill Blue butterfly Polyommatus coridon in the UK: the impacts of conservation policies and environmental factors". Journal of Insect Conservation. 12 (6): 629–638. doi:10.1007/s10841-007-9099-0. ISSN1366-638X. S2CID22067588.