008000000a22002050004500 PH-MaWHO 20241108112340.0 WHO Scientific Group on Epidemiology, Etiology, and Prevention of Periodontal Diseases (1977 : Moscow). 657352 Epidemiology, etiology, and prevention of periodontal diseases : report of a WHO scientific group [meeting held in Moscow from 23 November to 2 December 1977]. 92-4-120621-7 Geneva : World Health Organization, 1978. (WHO technical report series ; 621) 60p. WHO/HQ File eng Periodontal diseases 269177 World Health Organization 657353 http://whqlibdoc.who.int/trs/WHO_TRS_621.pdf MONO 8228 8228 0 0 0 0 WPRO WPRO 2021-05-23 0 WHO/HQ File 08228 2024-01-24 00:00:00 2021-05-23 MONO