Omkar Kumar, A.M. Latare, S.K. Singh. 2019. “Impact of Sewage Sludge Application on Soil Fertility, Microbial Population and Enzyme Activities in Soil under Rice-Wheat System”. Journal of the Indian Society of Soil Science 66 (3). https://epubs.icar.org.in/index.php/JISSS/article/view/86462.