1. Radiation hygiene and practice in dentistry: state regulation of dental X rays;JADA,1968
2. A survey of radiation received by dentists and dental assistants;Spalding;Amer Industr Hyg Assn J,1959
3. Radiation hygiene and practice in dentistry III;JADA,1968
4. Sources of X-radiation in the dental office;Richards;Dent Radiogr and Photogr,1964
5. X-ray protection in the dental office;Richards;JADA,1958