SINGH, KALYAN, E YOSHIMURA, K KANAZAWA, P C SUDHAKAR, and S MORI. 2014. “Effect of Organic Acid Ligands on Nutrient Mobilization from Volcanic Acid Soils”. The Indian Journal of Agricultural Sciences 71 (12). https://epubs.icar.org.in/index.php/IJAgS/article/view/40509.