1. Reports of the Committee for the Investigation of Dental Disease—II. Incidence of dental disease in children;Ainsworth,1925
2. Measurement of gingivitis among school age children in Brantford, Sarnia and Stratford using the P.M.A. index;Brown;J. Canad. dent. Ass.,1954
3. Studies on the incidence and cause of dental defects in children—III. Gingivitis;Bruckner;J. dent. Res.,1943
4. Incidence of dental caries among adults and young children in three high- and three low-fluoride areas in England;Forrest;Mon. Bull. Minist. Hlth,1951
5. Gingivitis in school children;Goose;Publ. Hlth. Lond.,1956