GABRIEL, Erwin.
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<strong>Philippine Engineering Journal</strong>, [S.l.], v. 39, n. 1, june 2018.
ISSN 2718-9287.
Available at: &lt;<a href="https://journals.upd.edu.ph/index.php/pej/article/view/6202" target="_new">https://journals.upd.edu.ph/index.php/pej/article/view/6202</a>&gt;. Date accessed: 01 sep. 2025.