Sopianah, Ani, Sukarni Novita Sari, and Juardi. 2025. “Cost Control Function in Operational Cost Efficiency at Squid Restaurant By Grandin Hotel Grand Dafam Ancol Jakarta”. Journal of Sustainable Tourism and Hotel Management 1 (1):52-64. https://journal.idscipub.com/index.php/sthm/article/view/473.