Susanto, Primadi Candra, and Ryan Firdiansyah Suryawan. 2021. “OPTIMALISASI DAN KONTRIBUSI USAHA TRAVEL AGENT KEPADA MASKAPAI PENERBANGAN DI MASA PANDEMI COVID-19”. Premium Insurance Business Journal 8 (1), 46 -51. http://ejournal.stma-trisakti.ac.id/index.php/premium/article/view/14.