1. Reliability and dispersion of nasality ratings;Counihan;Cleft Palate J.,1970
2. Basic Statistical Methods;Downey,1970
3. Voice and Articulation Drillbook;Fairbanks,1960
4. Resonance and phonation;Fletcher;Cleft Palate J.,1977
5. Lass, N.J. (1977). Personal communication.