Piwowarczyk, Renata. 2012. “Revised Distribution and Phytosociological Data of Orobanche Coerulescens Stephan in Willd. (Orobanchaceae): Poland in Relation to Central Europe”. Biodiversity: Research and Conservation 26 (November):61-72. https://doi.org/10.2478/v10119-012-0007-4.