Vijaya Gopal, A., S.K. Gosal, and Jupinder Kaur. 2021. “Diversity of Nitrogen Fixing Bacteria in Rhizospheric Soils of citrus–poplar Cropping System of Punjab”. Indian Journal of Agroforestry 23 (1). https://epubs.icar.org.in/index.php/IJA/article/view/114608.