- Leach and Green1
- Lincoln and Luchesi1
- MacGregor Instrument Company1
- Madden, Joseph W., MD1
- Mailhouse, Robert1
- Marra, Jodi (1999) (Branford, CT)1
- Mashied a Paris1
- Master Electric Company1
- Max Levy1
- McIntire, Magee and Brown Company1
- Meyrowitz Brothers1
- Miller, Robert1
- Optische Werke C. Reichert1
- Otto and Reynders1
- P. G. Williams1
- Pastorelli and Rapkin, Ltd.1
- Pratt, N. J. (Bridgeport, CT)1
- Pratt, N. J., MD1
- R. Utlzmann, MD1
- Reed and Company1
Libraries & Collections
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