Gostin, Irina, and Adrian Oprea. “Anatomical Investigations on Endemic Campanula Romanica Savul. And Their Ecological Significance”. Bangladesh Journal of Botany 42, no. 1 (July 28, 2013): 139–144. Accessed October 7, 2022. https://www.banglajol.info/index.php/BJB/article/view/15877.