QUIRIT, Leni L.; 						HERNANDEZ, Karen N.; 						LEE, Brian J..
 Comparison of Several Methods for Nitrogen Dioxide and Sulfur Dioxide in Metro Manila Air.
<strong>Science Diliman: A Journal of Pure and Applied Sciences</strong>, [S.l.], v. 19, n. 2, jan. 2008.
ISSN 2012-0818.
Available at: &lt;<a href="https://www.journals.upd.edu.ph/index.php/sciencediliman/article/view/710" target="_new">https://www.journals.upd.edu.ph/index.php/sciencediliman/article/view/710</a>&gt;. Date accessed: 05 sep. 2025.