AbdulGhani Gaghman. “Learning from Royal Shell’s Logistics and Supply Chain Management”. Konfrontasi: Jurnal Kultural, Ekonomi dan Perubahan Sosial 7, no. 1 (March 3, 2020): 91-104. Accessed May 26, 2020. http://konfrontasi.net/index.php/konfrontasi2/article/view/100.