Franz K. Huber, Roman Kaiser, Willi Sauter, Florian P. Schiestl: Floral scent emission and pollinator attraction in two species of Gymnadenia (Orchidaceae). In: Oecologia, Band 142, 2005, S. 564–575, doi:10.1007/s00442-004-1750-9 (PDF).
Franz K. Huber, Roman Kaiser, Willi Sauter, Florian P. Schiestl: Floral scent emission and pollinator attraction in two species of Gymnadenia (Orchidaceae). In: Oecologia, Band 142, 2005, S. 564–575, doi:10.1007/s00442-004-1750-9 (PDF).