Z. Kassab-Bashi, A., Th. Saieed, N. and M. Omar, O. 2014. Doubling the Chromosome Number of Black Poplar Trees (Populus nigra L.) by Colchicine In vitro. Rafidain Journal of Science. 25, 5 (Oct. 2014), 1–16. DOI:https://doi.org/10.33899/rjs.2014.131363.