Wright, H.N., and Fenske, E.L.: Factors Involved in Variability in Hardness of Tooth Structures, J. D. Res. 17: 297, 1938.
2.
Hodge, H.C., and McKay, H.: The Microhardness of Teeth, J. A. D. A. 20: 227, 1933.
3.
Zieger, W.: Dissertation, Halle, 1934.
4.
Richter, H.: Härteprufüng an Schmelz und Dentin. II. Über Ritz und Kugeldruckhärte der harten Zahnsubstanzen-Ein kritischer Vergleich, Ztschr. Stomatol . 29: 591, 1931.
5.
Proell, F.W., and Schubert: Die Ritzharte des Schmelzes, Ztschr. Stomatol . 26: 1047, 1928.
6.
Craig, R.G., and Peyton, F.A.: The Microhardness of Enamel and Dentin, J. D. Res. 37: 661, 1958.
7.
Lunt, D.A.: A Modified Pollak Trichrome Method for the Staining of Ground Sections of Teeth, Brit. D. J. 104: 17, 1958.
8.
Van Huysen, G., Hodge, H.C., Warren, S.L., and Bishop, F.W.: Quantitative Roentgen-Ray Study of Certain Pathological Changes in Dentin, D. Cosmos75: 729, 1933.
9.
Van Huysen, G., Bale, W.F., and Hodge, H.C.: Comparative Study of the Roentgen-Ray Absorption Properties of Normal and Pathological Dentin, D. Cosmos77: 146, 1935.
10.
Hodge, H.C. : Microhardness Studies on Transparent Dentin, Brit. D. J. 63: 181, 1937.
11.
Buchbinder, M.: Porosity of Root Canal Dentin, J. D. Res. 32: 724, 1953.
