- Correspondence of Wagner and Liszt — Volume 2Author: Richard Wagner, Franz Liszt, Francis HuefferReleased on Project Gutenberg: July 1, 2003
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- Cosmopolis — CompleteAuthor: Paul BourgetReleased on Project Gutenberg: October 30, 2004
- Cosmopolis — Volume 1Author: Paul BourgetReleased on Project Gutenberg: April 1, 2003
- Cosmopolis — Volume 2Author: Paul BourgetReleased on Project Gutenberg: April 1, 2003
- Cosmopolis — Volume 3Author: Paul BourgetReleased on Project Gutenberg: April 1, 2003
- Cosmopolis — Volume 4Author: Paul BourgetReleased on Project Gutenberg: April 1, 2003
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- Count Alarcos; a TragedyAuthor: Disraeli, Benjamin, Earl of BeaconsfieldReleased on Project Gutenberg: February 1, 2005
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- Count JulianAuthor: Walter Savage LandorReleased on Project Gutenberg: May 1, 2003
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- Counter-Attack and Other PoemsAuthor: Siegfried SassoonReleased on Project Gutenberg: September 1, 2005
- Countess KateAuthor: Charlotte M. (Charlotte Mary) YongeReleased on Project Gutenberg: June 1, 2002
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- Country LodgingsAuthor: Mary Russell MitfordReleased on Project Gutenberg: October 2, 2007
- Country NeighborsAuthor: Alice BrownReleased on Project Gutenberg: February 7, 2008
- Country SentimentAuthor: Robert GravesReleased on Project Gutenberg: August 1, 1998
- Country Walks of a Naturalist with His ChildrenAuthor: W. (William) HoughtonReleased on Project Gutenberg: December 20, 2007
- CourageAuthor: J. M. (James Matthew) BarrieReleased on Project Gutenberg: January 1, 2004
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- Cousin HenryAuthor: Anthony TrollopeReleased on Project Gutenberg: January 1, 2008
- Cousin MaudeAuthor: Mary Jane HolmesReleased on Project Gutenberg: January 1, 2003
- Cousin PhillisAuthor: Elizabeth Cleghorn GaskellReleased on Project Gutenberg: July 1, 2003
- Cousin PonsAuthor: Honoré de Balzac, Ellen MarriageReleased on Project Gutenberg: August 1, 1999
- Cow-CountryAuthor: B. M. BowerReleased on Project Gutenberg: April 1, 1999
- Cowboy Dave; Or, The Round-up at Rolling RiverAuthor: Webster, Frank V.Released on Project Gutenberg: July 1, 2004
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- Cowley's EssaysAuthor: Abraham CowleyReleased on Project Gutenberg: November 1, 2002
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- Crime and Its CausesAuthor: William Douglas MorrisonReleased on Project Gutenberg: May 9, 2005
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- Criminal NegligenceAuthor: J. Francis McComas, Kelly FreasReleased on Project Gutenberg: January 22, 2008