Ombódi, A., and M. Saigusa. “Reducing Nitrate Content in Lettuce Using Polyolefin-Coated Fertilizers”. International Journal of Horticultural Science 6, no. 4 (August 23, 2000): 35–38. Accessed May 4, 2024. https://ojs.lib.unideb.hu/IJHS/article/view/214.