Iamsirithaworn, S., P. Akarasewi, T. Yingyong, S. Suthachana, C. Pittayawonganon, and K. Ungchusak. “Three Waves of the 2009 H1N1 Infl uenza Pandemic in Thailand”. Siriraj Medical Journal, vol. 63, no. 2, Apr. 2020, pp. 64-67, https://he02.tci-thaijo.org/index.php/sirirajmedj/article/view/240910.