1. Bureau of Biologics, Food and Drug Administration, Bethesda, Maryland 20205
2. Department of Pediatrics, Charlotte Memorial Hospital, Charlotte, North Carolina 28232
3. Department of Microbiology and Immunology, Downstate Medical Center, State University of New York, Brooklyn, New York 11203
4. World Health Organization Collaborating Center for Reference and Research on Pneumococci, Statens Seruminstitut, Copenhagen, Denmark
5. Department of Research, University of Pennsylvania, Philadelphia, Pennsylvania 19104