Ong, Johan Oscar, and Suprayogi . “Vehicle Routing Problem With Backhaul, Multiple Trips and Time Window”. Jurnal Teknik Industri: Jurnal Keilmuan dan Aplikasi Teknik Industri 13, no. 1 (June 11, 2011): 1-10. Accessed May 6, 2024. https://jurnalindustri.petra.ac.id/index.php/ind/article/view/18148.