M. Majeed, Bushra. “Comparison of Letrozole With Gonadotropins and letrozole_gonadotropin Combination for Ovulation Induction in PCOS Women After Clomiphene Citrate Failure”. Tikrit Journal of Pharmaceutical Sciences, vol. 9, no. 1, Apr. 2023, pp. 54-60, doi:10.25130/tjphs.2013.9.1.6.54.60.