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<strong>Philippine Engineering Journal</strong>, [S.l.], v. 24, n. 2, aug. 2011.
ISSN 2718-9287.
Available at: &lt;<a href="https://www.journals.upd.edu.ph/index.php/pej/article/view/2500" target="_new">https://www.journals.upd.edu.ph/index.php/pej/article/view/2500</a>&gt;. Date accessed: 06 aug. 2025.