- John B. Daniel (Firm)1
- John C. Baker & Co.1
- John W. Perkins & Co.1
- Johnson, C. Lawson (Charles Lawson), 1886- author1
- Judkins, William, author1
- Kaufmann, Carl Ernst.1
- Launy, David Frederick.1
- Law, Hartland, author1
- Leaper, Percy J., author1
- Letterman General Hospital (San Francisco, Calif.), author.1
- Lord, Owen & Co.1
- M. S. (Moses Stringer)1
- MacKenzie, Colin, 1775?-18271
- Massachusetts College of Pharmacy, author.1
- Massachusetts Medical Society.1
- Mayne, John.1
- Medical Society of the State of New York (1807- )1
- Merck & Co.1
- Merrick, Billings & Otis.1
- Merrick, Otis & Co.1