Kunathikom, Somboon, Phakphum Phophong, Potjamarn Potjanakorn, Somchit Koanantakul, Roungsin Choavaratana, Singpetch Suksompon, Suphakde Julavijitphong, and Suwit Suppinyopong. 1998. “Hypo-osmotic Swelling Test and Sperm Motility after Swim-up and Two-layer Percoll Gradient Preparation of Frozen-Thawed Sperm”. Thai Journal of Obstetrics and Gynaecology 10 (1). Bangkok, Thailand:47-51. https://he02.tci-thaijo.org/index.php/tjog/article/view/257116.