“El Nino Effect on Coffee Growth and Productivity on Several Agroforestry Systems in Gumitir Mountain Coffee Farms, East Java, Indonesia”. Pelita Perkebunan (a Coffee and Cocoa Research Journal) 33, no. 3 (December 31, 2017): 168–179. Accessed May 1, 2026. https://www.ccrjournal.com/index.php/ccrj/article/view/.