Shanjani, Parvin Salehi, et al. “Effects of Water Stress on Germination of Yarrow Populations (Achilleaspp.) from Different Bioclimatic Zones in Iran”. Plant Breeding and Seed Science, vol. 68, Dec. 2013, pp. 39-54, http://ojs.ihar.edu.pl/index.php/pbss/article/view/292.