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Ramos-Alvarez M, Sabin AB. Enteropathogenic viruses and bacteria; role in summer diarrheal diseases of infancy and early childhood. J. Am. Med. Assoc. 167: 147-156, 1958. PubMed: 13538681

Wigand R, Sabin AB. Antigenic purity and plaque properties of the prototype strains of ECHO virus types 7 to 11, and 17 and 18. Arch. Gesamte Virusforsch. 11: 708-717, 1962. PubMed: 14040255