Reference

P. Arduino, Rossella Cianchi, Walter Rossi, B. Corrias, Luciano Bullini (1995): Genetic variation in Orchis papilionacea (Orchidaceae) from the Central Mediterranean region: taxonomic inferences at the intraspecific level – Österreichische Botanische Zeitschrift = Plant Systematics and Evolution – 194: 9 - 23.