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2. Velopharyngeal function in cleft palate;Skolnick;Clin Plast Surg,1975
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4. Hypertrophic tonsils: the effect on resonance and velopharyngeal closure;Kummer;Plast Reconstr Surg,1993
5. Hypernasality (rhinolalia aperta) following tonsil and adenoid removal;Gibb;J Laryngol Otol,1958