Afridi, Nighat, et al. “COMPARISON OF EFFICACY OF ORAL PROGESTERONE AND MICRONIZED PROGESTERONE PESSARY IN REDUCTION OF INCIDENCE OF SPONTANEOUS PRETERM BIRTHS”. Journal of Ayub Medical College Abbottabad, vol. 31, no. 2, Mar. 2019, pp. 248-51, https://jamc.ayubmed.edu.pk/index.php/jamc/article/view/6187.