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- Comstock, C. B. (Cyrus Ballou), 1831-19101
- Conder, C. R. (Claude Reignier), 1848-19101
- Conder, T.1
- Cooley, George W.(George Washington)1
- Cope, Emmor B1
- Copp Clark Company1
- Corbett & Skidmore Co.1
- Coronelli, Vincenza Maria, 1650-17181
- Coronelli, Vincenzo, 1650-17181
- Cousin, Paul1
- Coy, Owen Cochran, 1884-19521
- Craddock, Campbell1
- Credner, Heinrich, 1809-18761
- Creighton, Roger (Draftsman)1
- Criado, M. Alonso1
- Crosby, John Q. A1
- Crowell Publishing Company1
- Crown Estate Commissioners (Great Britain)1