SANDHYA, K MADHUSUDHANAN, B A RAHIMAN, B. 1996. “In Vitro Culture of Piper Attenuatum Ham. (Piperaceae): Callus Induction and Plant Regeneration”. Journal of Spices and Aromatic Crops 5 (2):127-30. https://www.updatepublishing.com/journal/index.php/josac/article/view/4385.