Widjaya, Dani, Yuli Hariyati, and Djoko Soejono. 2017. “Technical and Economic Efficiency of Smallholder Arabica Coffee Farming in Panti Sub-District, Jember”. Pelita Perkebunan (a Coffee and Cocoa Research Journal) 33 (1), 51-56. https://doi.org/10.22302/iccri.jur.pelitaperkebunan.v33i1.255.