1. Schluger S, Yvodelis RA, Page RC. Periodontal D i s e a s e : B a s i c P h e n o m e n a , C l i n i c a l Management, and Occlusal and Restorative Relationships. Philadelphia: Lea and Febiger; 1978:491.
2. Prichard JF. Advanced Periodontal Disease: Surgical and Prosthetic Management, 2nd ed. Philadelphia: W.B. Saunders Co.; 1972:461-462.
3. Corn H. Mucogingival surgery and associated problems. In: Goldman HM, Cohen DW, eds. Periodontal Therapy, 4th ed. St. Louis: The C.V. Mosby Co; 1980:1033.