1. Why crowns?;Simonsen;Quintessence Int,1995
2. 1990 Census of population, social and economic characteristics,1990
3. Contemporary fixed prosthodontics;Rosenstiel,1988
4. Esthetics: a multidisciplinary approach;Spear,1991
5. Clinical and microbiological effects of subgingival restorations with overhanging or clinically perfect margins;Lang;J Clin Periodontol,1983