Techarungpaisan, Pisit, Asoke Shithongtum, Bancha Buddadee, Songsupa Pumchumpol, and Songsupa Pumchumpol. 2017. “Performance improvement of thermosyphon solar water heater: minimizing water flow rate in some risers of the solar collector (Thai)”. Asia-Pacific Journal of Science and Technology 14 (1):41-54. https://so01.tci-thaijo.org/index.php/APST/article/view/83090.