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Publisher
- Advanstar Communications2
- American Heart Association1
- American Society for Microbiology2
- Association for Academic Health Centers1
- Charles B. Slack, Inc.2
- Excerpta Medica (Firm)1
- Hahnemann University1
- Howard Hughes Medical Institute2
- Interactive Media1
- Massachusetts Medical Society1
- McGraw-Hill Companies1
- National Academy of Sciences (U.S.)1
- National Institutes of Health (U.S.)5
- New England journal of medicine1
- New York Times Company2
- Pergamon Press, Inc.1
- Publications de L' Academie du Royaume du Maroc Collection1
- Royal Gorge Publishing Corporation2
- The Foundation Conchita Rabago1
- Time, Inc.1