Reference
Herbert Braunschmid, Bernadette Mükisch, Thomas Rupp, Irmgard Schäffler, Pietro Zito, Daniele Birtele, Stefan Dötterl (2017): Interpopulation variation in pollinators and floral scent of the lady´s-slipper orchid Cypripedium calceolus L. – Arthropod-Plant Interactions 11 – Monografien Entomologie Hymenoptera – 0206: 363 - 379.