Virus Tumorigenesis and Immunogenesis: proceeding of a conference on virus Timorigenesis and immunogenesis held at Pennsyl vania state University, Pennsylvania, April 6-8, 1972 edited Walter S. Ceglowski , Herman Friedman. - Proceeding of a conference on virus Timorigenesis and immunogenesis held at Pennsyl vania state University, Pennsylvania, April 6-8, 1972 (New York Academic Press, 1973)