Klislinar , Ermila, and Anton Wachidin Widjaja. “Analysis of Willingness to Pay for Ancillary Revenue of Full Service Airline (The Case of Garuda Indonesia)”. KnE Social Sciences 4, no. 6 (March 23, 2020): 1213–1230. Accessed June 2, 2020. https://knepublishing.com/index.php/KnE-Social/article/view/6672.