Susilo, Wilhelmus Hary, and Lili Suryaty. “Analysis Hybrid Model: An Influencing Marketing 3.0 to Purchasing on Postgraduate Program Institutions in Jakarta”. International Journal of Economics and Financial Issues, vol. 5, no. 1S, July 2015, pp. 165-71, https://mail.econjournals.com/index.php/ijefi/article/view/1382.