Fairchok M. P., Martin E. T., Chambers S., Kuypers J., Behrens M., Braun L. E., Englund
J. A., 2010, Epidemiology of Viral Respiratory Tract Infections in a Prospective Cohort
of Infants and Toddlers Attending Daycare, Journal of Clinical Virology, Vol. 49,
No. 1, pp. 16-20