B. Kheonkaew, W. Wichatorntrakul, E. Mairiang, P. Awikhunprasert, and K. Nikapruek, “The assessment of exposure index on the posterior-anterior computed radiography chest in Srinagarind Hospital, Khon Kaen University”, J Assoc Med Sci, vol. 47, no. 1, p. 23, Jan. 2014.