Amarah Batool,  Ijaz Rasool Noorka, Muhammad Afzal , and Ali Hassan Syed. “Estimation of Heterosis, Heterobeltiosis and Potence Ratio Over Environments Among Pre and Post Green Revolution Spring Wheat in Pakistan”. Journal of Basic & Applied Sciences, vol. 9, Jan. 2013, pp. 36-43, doi:10.6000/1927-5129.2013.09.07.