1. Braden, M., J. Dent. Res., 1974, 53, 1089 (Abst).
2. Brudevold, F., Savory, A., Gardner, D. E., Spinelli, M. and Speirs, R., Arch. Oral Biol., 1963, 8, 167.
3. Clarkson, B. H. and Silverstone, L. M., J. Int. Assoc. Dent. Child., 1974, 5, 27.
4. Cox, G. J. and Hodge, H. C., J. Am. Dent. Assoc, 1950, 40, 440.
5. Muhler, J. C., J. Periodont., 1957, 28, 281.