Yormprakhon, Santi, Doungrut Wattanakitkrileart, Kanaungnit Pongthavornkamol, and Charoen Chuchottaworn. 2014. “The Influence of Health Literacy, Perceived Social Support, and Uncertainty in Illness on Functional Status in Patients With Chronic Obstructive Pulmonary Disease”. Nursing Science Journal of Thailand 32 (3):64-73. https://he02.tci-thaijo.org/index.php/ns/article/view/27337.