1. 2. M. Rajala Occurrence of tooth loss, dental caries and need of operative dental treatment in an industrial population. Kuopio: Publications of the University of Kuopio. Community Health. Series Original Reports 2/1977.103 pp. Dissertation.
2. 3. PE. Petersen, Dental health behavior, dental health status and dental treatment needs among workers and staff-members of a Danish shipyard: a socio-dental industrial investigation . Odense: Odense University Press, 1981 . 332 pp.Dissertation.
3. Oral health of workers in the modern Finnish confectionery industry
4. 5. P. Alanen, Vertaileva tutkimus subvention vaikutuksesta hampaiden kuntoon ja hammashoitopalvelujen kaytoon. (The effect of subvention on dental care, a clinical study) . Turku: Institute of Dentistry. University of Turku, 1982 . 110 pp. Dissertation.