Väisänen, R., Heliövaara, K. and Somerma, P. 1994. Wing variation of Maculinea arion (Linnaeus) in Finland (Lepidoptera, Lycaenidae). Entomologica Fennica. 5, 3 (Sep. 1994), 139–146. DOI:https://doi.org/10.33338/ef.83809.