Lim, H.S., Y.S. Ko, D.S. Shin, Y.R. Heo, H.J. Chung, I.S. Chae, H.Y. Kim, M.H. Kim, D.G. Leem and Y.K. Lee. 2013. Sodium and potassium content of school meals for elementary and junior high school students in Daegu, Masan, Gwangju, and Jeju. J. Kor. Soc Food Sci Nutr. 42(8):1303-1317 (in Korean).