Fifty Years Ago in Spine …

References 

1. Salk JE, Bennett BL, Lewis LJ, et al.  Studies in human subjects on active immunization against poliomyelitis. A preliminary report of experiments in progress. JAMA. 1953;151:1081–1098
2. Sabin AB. Characteristics and genetic potentialities of experimentally produced and naturally occurring variants of poliomyelitis virus. Ann NY Acad Sci. 1955;61:924–938