P. Wongkrajang, W. Chinswangwatanakul, P. Tientadakul, and N. Opartkiattikul, “Whole Blood Clotting Time: Variation of Practice in Coagulation Laboratory, Members of Thailand National External Quality Assessment Scheme”, Siriraj Med J, vol. 63, no. 3, pp. 81–84, Apr. 2020.