PT - JOURNAL ARTICLE AU - Donald G. Vidt TI - Introduction DP - 1975 Sep 21 TA - Cleveland Clinic Journal of Medicine PG - 215--216 VI - 42 IP - 3 4099 - http://www.ccjm.org/content/42/3/215.short 4100 - http://www.ccjm.org/content/42/3/215.full SO - Cleve Clin J Med1975 Sep 21; 42