Helper-independent mink cell focus-inducing strains of Friend murine type-C virus: potential relationship to the origin of replication-defective spleen focus-forming virus.
Troxler DH, Yuan E, Linemeyer D, Ruscetti S, Scolnick EM. Helper-independent mink cell focus-inducing strains of Friend murine type-C virus: potential relationship to the origin of replication-defective spleen focus-forming virus. J Exp Med. 1978 Sep 01; 148(3):639-53.