Pushpangathan, C., and A. R. Moosvi. “Earth Observation Techniques for Assessing the Vegetation Health Conditions of Major Cropping Seasons in Kalaburagi District, Karnataka, India”. Thematics Journal of Geography, Vol. 8, no. 10, Oct. 2019, pp. 122-3, http://www.thinkindiaquarterly.org/index.php/tjg/article/view/9249.