Discussion of ¿Mechanical Strength Improvement of Cement-Stabilized Soil Using Natural Rubber Latex for Pavement Base Applications¿ by Apinun Buritatun, Thaworn Takaikaew, Suksun Horpibulsuk, Artit Udomchai, Menglim Hoy, Nopparat Vichitcholchai, and Arul Arulrajah