1. Al’okhin, O.O., Gaponenko, M.B., and Sobko, V.G., Orkhidei Dalekogo Skhodu (Orchids of the Far East), Kiev: Fitosiotsotsentr, 2003.
2. Arbeitskreise Heimische Orchideen (Hrsg.): Die Orchideen Deutschlands, Uhlstädt-Kirchhasel, 2005.
3. Aver’yanov, L.V., Speciation and variability of species from the genus Gymnadenia R.Br. in the northern part of the range, Biologicheskie problemy Severa: Tez. dokl. IX mezhdunar. simpoziuma (Biological Problems in the North: Abstr. IX Int. Symp.), Syktyvkar, 1981, part 1, p. 10.
4. Bateman, R.M. and Rudall, P.J., Evolutionary and morphometric implications of morphological variation among flowers within an inflorescence: A case-study using European orchids, Ann. Bot., 2006, vol. 98, pp. 975–993.
5. Blinova, I.V., Specific features of ontogeny in some roottuber orchids (Orchidaceae) in the Extreme North, Bot. Zh., 1998, vol. 83, no. 1, pp. 85–94.