H.A.Pedersen (E.G.Camus) 2006 - Pedersen HÆ (2006) Systematics and evolution of the Dactylorhiza romana/sambucina polyploid complex (Orchidaceae). Botanical Journal of the Linnean Society 152(4): 405-434. doi: 10.1111/j.1095-8339.2006.00573.x.