1. Dental survey of Philadelphia preschool children by income, age and treatment status;Wisan;JA.D.A.,1957
2. Caries susceptibility tests, hyaluronidase activity of saliva and dental caries experience;Rovelstad;J.D. Res.,1958
3. Dental caries experience in Philadelphia school children;Cohen;J. Den. Children,1952
4. Howell, C. L. An observation of the reduction in dental needs in a group of children attending 4H Club camps in Indiana. Personal communication.