1. Den Norske Befolkningsstatistikk;Backer;Statistiske Meddelelser,1947
2. Rheumatic Heart Disease as a Problem of preventive cardiology;Biörck;J. Chron. Dis.,1955
3. Rheumatic Fever Statistics in Denmark from 1878 to 1946 and their Significance in Profylaxis;Clemmensen;Act. Med. Scand.,1949
4. Rheumatic Fever with Chorea Minor;Jacobbson;Act. Paed.,1946