Somchai Thongphua. (1999) Serological response to sequential doses of enhanced-potency inactivated polio vaccine and oral polio vaccine schedules. Mahidol University,:ม.ป.ท.Somchai Thongphua. 1999. Serological response to sequential doses of enhanced-potency inactivated polio vaccine and oral polio vaccine schedules. ม.ป.ท.:Mahidol University,;Somchai Thongphua. Serological response to sequential doses of enhanced-potency inactivated polio vaccine and oral polio vaccine schedules. ม.ป.ท.:Mahidol University, 1999. Print.