1. Specification No. 52 for Uranium content in dental porcelain and porcelain teeth;J. Am. Dent. Assoc.,1979
2. Specification No. 69. Dental ceramic, council on dental materials, instruments and equipments;American Dental Association,1991
3. Potassium compounds for gamma spectrometer efficiency verification;Belgin;Appl. Radiat. Isot.,2017
4. Civil use of depleted uranium;Betti;J. Environ. Radioact.,2003
5. Radioactivity in raw materials and end products in the Italian ceramic industry;Bruzzi;J. Environ. Radioact.,2000