1. The increase with age of the width of attached gingiva;Ainamo;J Periodontal Res,1976
2. Periodontal tissue reactions to orthodontic extrusion;Berglundh;J Clin Periodontol,1991
3. Tratamiento quirurgico de la paradentosis. Thesis;Carranza;Anals Atoneo Instituto Municipal Odontol (Buenos Aires),1935
4. Periodontal regeneration;Caton;Periodontol 2000,1993