LAWRENCE, G M NAIR, V. S. E. T. B. “Plant Regeneration in Piper Longum L. (Piperaceae) through Direct and Indirect Adventitious Shoot Development”. Journal of Spices and Aromatic Crops, vol. 2, no. 1, Dec. 1993, pp. 34-40, https://updatepublishing.com/journal/index.php/josac/article/view/4311.