Pornkana Sonthilawat. (1992) Study of nasopharyngeal airway and its relationship to craniofacial structures in Thai. Mahidol University,:ม.ป.ท.Pornkana Sonthilawat. 1992. Study of nasopharyngeal airway and its relationship to craniofacial structures in Thai. ม.ป.ท.:Mahidol University,;Pornkana Sonthilawat. Study of nasopharyngeal airway and its relationship to craniofacial structures in Thai. ม.ป.ท.:Mahidol University, 1992. Print.