Johan, J. et al. 2010. Analisis dan Perancangan Aplikasi Pendukung Erp Sap R/3 Modul Sales and Distribution PT. United Tractors, Tbk. ComTech: Computer, Mathematics and Engineering Applications. 1, 2 (Dec. 2010), 645–655. DOI:https://doi.org/10.21512/comtech.v1i2.2564.