VILLEGAS, Edberto M..
 The Modern Principalia: The Historical Evolution of the Philippine Ruling Oligarchy by Dante C. Simbulan.
<strong>Philippine Political Science Journal</strong>, [S.l.], v. 30, n. 53, july 2009.
ISSN 0115-4451. Available at: &lt;<a href="https://journals.upd.edu.ph/index.php/ppsj/article/view/1340" target="_new">https://journals.upd.edu.ph/index.php/ppsj/article/view/1340</a>&gt;. Date accessed: 29 aug. 2025.