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- Shannon, Thomas W. (Thomas Washington), 1866- author2
- Shields, M. J. (Matthew Joseph), 1862-1939, author3
- Sidis, Boris, 1867-1923, author1
- Silva, Alpheu Olympio da, author1
- Silva, Arsenio L. Tavares da, author1
- Silva, Maurilio Pinto da, author1
- Silva, Virgilio Pereira da, author1
- Silveira, Carlos Cavalcanti da, author1
- Silveira, Manoel Sotero Vaz de, author1
- Simon, William, 1844-19161
- Small, Willard S. (Willard Stanton), 1870-19431
- Smith, Alexander, 1865-19222
- Smith, Amy Armour, author1
- Smith, Fred M., 1888-1
- Society of the Lying-In Hospital of the City of New-York, author.1
- Souza, Antonio Pacifico Pereira de, author1
- Souza, Eduardo Borba e, author1
- Stanton, Mary Olmstead, author1
- Stearns, Guy Beckley.1