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Authors
- National Eye Institute.22
- National Library of Medicine (U.S.). Board of Regents.3
- National Library of Medicine (U.S.). Division of Extramural Programs.2
- Billings, F. S. (Frank Seaver), 1845-1912 author1
- National Library of Medicine (U.S.) author, issuing body.1
- National Library of Medicine (U.S.). Board of Regents, author.1