1. Observations on the dose from dental X-ray procedures with a note on radiography of the nasal bones;Ardran;Br. J. Radiol.,1959
2. A reproducible method for caries evaluation;Backer-Dirks;J. Dent. Res.,1951
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4. A new principle and appliance for radiographic tooth measurements;Benkow;J. Dent. Res.,1957
5. Diagnosis of hidden caries by means of the radiograph;Bodecker;Dental Rev. (Chicago),1912