“Cooperation Model of “Tampan”(dividing profit based on the agreement) and ‘Ounce’ (cooperation model based on the ounce scale in the Coconut Sugar Production: The Study of Coconut Sugar Produsen in Karang BendoVillage Ponggok District Blitar Regency” (2019) JOSAR (Journal of Students Academic Research), 4(1), pp. 72–83. doi:10.35457/josar.v4i1.749.