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- Peterson, Reuben, 1862-1942, author8
- Pliny, the Elder8
- Ponce, Ninez A., author8
- Porcher, Francis Peyre, 1825-18958
- Preston, George J. (George Junkin), 1858- author8
- Ramsay, David, 1749-18158
- Rauch, John H. (John Henry), 1828-18948
- Reed, Robert Harvey, 1851-1907, author8
- Robinson, Beverley, 1844-1924, author8
- Santos Fernández, Juan, 1847-1922, author8
- Schneider, Andy, author8
- Schüssler, Wilhelm Heinrich, 1821-18988
- Semanskee, Ashley, author8
- Shoemaker, John V. (John Veitch), 1852-1910, author8
- Sinkler, Wharton, 1845-1910, author8
- Snow, Edwin M. (Edwin Miller), 1820-1888, author8
- Suffolk District Medical Society (Suffolk County, Mass.)8
- Taylor, Charles Fayette, 1827-1899, author8