1. Telemetry of plaque pH from interdental area;Graf;Helv. odont. Acta,1966
2. The direct determination of fluoride in human saliva by a fluoride electrode;Grøn;Archs oral Biol.,1968
3. Der Einfluss von Fluortablettengaben in der Schule auf den Kariesbefall 6- bis 15 jähriger Kinder;Marthaler;Schweiz. Mschr. Zahnheilk.,1967
4. Fluoride concentrations in saliva during and after supervised toothbrushing with 1-percent sodium fluoride solution;Marthaler;Helv. odont. Acta,1968