Rumana Yeasmin, and Eiji Nishihara. “Activated Carbon and Phosphorus Application Influences the Growth of Continuously Replanted Asparagus (Asparagus Officinalis L.)”. Global Journal of Science Frontier Research, vol. 13, no. B5, Mar. 2013, pp. 1-7, https://journalofscience.org/index.php/GJSFR/article/view/902.