Bako Baon, John. “Identification of Soil Organic Nitrogen Substance Acting As Indicator of Response of Cocoa Plants to Nitrogen Fertilizer”. Pelita Perkebunan (a Coffee and Cocoa Research Journal) 24, no. 2 (July 31, 2008). Accessed October 19, 2024. https://mail.ccrjournal.com/index.php/ccrj/article/view/98.