300,510 RAMSTEDT KRISTINA An epidemiological approach to Sexually Transmitted Diseases - with special reference to contact tracing and screening : [thesis] / Kristina Ramstsdt. Göteborg : Departament of Dermato-Venereology, University of Göteborg, 1991. - 54 s. : wykr. ; 25 cm (Acta Dermato-Venerologica, ISSN 0365-8341 ; suppl. 157)