Singh, S., Mohan, U., Shukla, N., Pandey, S., Singh, S. S., Pandey, U. S., & Tiwari, S. (1995). Case control study of Electrocardiographic changes in pregnant women. Indian Journal of Community Health, 8(2,3), 24–27. Retrieved from http://iapsmupuk.org/journal/index.php/IJCH/article/view/28