Ritonga, Husni Muharram. “Analysis Tourist Satisfaction on Bukit Kubu, Berastagi North Sumatera, Indonesia”. The International Journal of Business & Management 7, no. 10 (October 31, 2019). Accessed July 22, 2024. https://internationaljournalcorner.com/index.php/theijbm/article/view/149059.