Piyasak Vitayaburananont และ Pruchwilai Nuchpramool. (2020) Assess Level of Post-operative Pain in Adult Patients who Underwent Elective Surgery Using Pre-printed Postoperative Pain Order in Vajira Hospital. <i>Vajira Medical Journal</i>, <i>64</i>(2), 125-132.Piyasak Vitayaburananont และ Pruchwilai Nuchpramool. "Assess Level of Post-operative Pain in Adult Patients who Underwent Elective Surgery Using Pre-printed Postoperative Pain Order in Vajira Hospital". Vajira Medical Journal 64 (2020):125-132.Piyasak Vitayaburananont และ Pruchwilai Nuchpramool. Assess Level of Post-operative Pain in Adult Patients who Underwent Elective Surgery Using Pre-printed Postoperative Pain Order in Vajira Hospital. Text and Journal Publication:ม.ป.ท. 2020.