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Zaidi M, Ponce de León S, Ortiz RM, Ponce de León S, Calva JJ, Ruiz-Palacios G, Camorlinga M, Cervantes LE, Ojeda F.Zaidi M, et al. Among authors: calva jj.Infect Control Hosp Epidemiol. 1991 Jun;12(6):349-55. doi: 10.1086/646355.Infect Control Hosp Epidemiol. 1991.PMID: 1906497
López-Vidal Y, Calva JJ, Trujillo A, Ponce de León A, Ramos A, Svennerholm AM, Ruiz-Palacios GM.López-Vidal Y, et al. Among authors: calva jj.J Infect Dis. 1990 Aug;162(2):442-7. doi: 10.1093/infdis/162.2.442.J Infect Dis. 1990.PMID: 1973696