- Original Short Stories — Volume 09Author: Guy de Maupassant, Henderson, A. E. [Translator], McMaster, Albert Cohn [Translator], Quesada, Louise Charlotte GarstinLanguage: English
- Original Short Stories — Volume 10Author: Guy de Maupassant, Henderson, A. E. [Translator], McMaster, Albert Cohn [Translator], Quesada, Louise Charlotte GarstinLanguage: English
- Original Short Stories — Volume 11Author: Guy de Maupassant, Henderson, A. E. [Translator], McMaster, Albert Cohn [Translator], Quesada, Louise Charlotte GarstinLanguage: English
- Original Short Stories — Volume 12Author: Guy de Maupassant, Henderson, A. E. [Translator], McMaster, Albert Cohn [Translator], Quesada, Louise Charlotte GarstinLanguage: English
- Original Short Stories — Volume 13Author: Guy de Maupassant, Henderson, A. E. [Translator], McMaster, Albert Cohn [Translator], Quesada, Louise Charlotte GarstinLanguage: English
- Orjan oppiAuthor: Arvid JärnefeltLanguage: Finnish
- Orjien vapauttaminen Pohjois-AmerikassaAuthor: Gripenberg, Alexandra, friherrinnaLanguage: Finnish
- Orlando FuriosoAuthor: Lodovico Ariosto, William Stewart RoseLanguage: English
- Orlando FuriosoAuthor: Lodovico AriostoLanguage: Italian
- Orley FarmAuthor: Anthony TrollopeLanguage: English
- Orpheu Nº1: Revista Trimestral de LiteraturaAuthor: António Joaquim Tavares Ferro, José de Almada Negreiros, Alvaro de Campos, Ronald de Carvalho, Armando César Cortes-RodriguesLanguage: Portuguese
- Orpheu Nº2: Revista Trimestral de LiteraturaAuthor: António Joaquim Tavares Ferro, Alvaro de Campos, Violante Cisneiros, Eduardo Guimarães, Raul de Oliveira Sousa LealLanguage: Portuguese
- Orpheus in Mayfair, and Other Stories and SketchesAuthor: Maurice BaringLanguage: English
- Orrain: A RomanceAuthor: Levett Yeats, S. (Sidney)Language: English
- OrthodoxyAuthor: G. K. (Gilbert Keith) ChestertonLanguage: English
- OrthodoxyAuthor: G. K. (Gilbert Keith) ChestertonLanguage: English
- OrthographyAuthor: Elmer W. (Elmer Warren) Cavins, Edwin C. (Edwin Crawford) HewettLanguage: English
- Os Bravos do Mindello: Romance HistoricoAuthor: Faustino da FonsecaLanguage: Portuguese
- Os deputados brasileiros nas Côrtes Geraes de 1821Author: Manuel Emílio Gomes de CarvalhoLanguage: Portuguese
- Os fidalgos da Casa Mourisca: Chronica da aldeiaAuthor: Júlio DinisLanguage: Portuguese
- Os Filhos do Padre AnselmoAuthor: António José da Costa Couto Sá de AlbergariaLanguage: Portuguese
- Os LusíadasAuthor: Camões, Luís deLanguage: Portuguese
- Os meus amores: contos e balladasAuthor: Trindade CoelhoLanguage: Portuguese
- Os Pobres: Precedido de uma Carta-Prefacio de Guerra JunqueiroAuthor: Raul Brandão, Abílio Manuel Guerra JunqueiroLanguage: Portuguese
- Os Primeiros Amores de Bocage: Comedia em Cinco ActosAuthor: José da Silva Mendes LealLanguage: Portuguese
- Os SimplesAuthor: Abílio Manuel Guerra JunqueiroLanguage: Portuguese
- Os Sinos: Poesia NarrativaAuthor: Raul Sangreman ProençaLanguage: Portuguese
- Os sonetos completos de Anthero de QuentalAuthor: Antero de QuentalLanguage: Portuguese
- Osage TraditionsAuthor: James Owen DorseyLanguage: English
- Oscar the Detective; Or, Dudie Dunne, The Exquisite DetectiveAuthor: Old SleuthLanguage: English
- Oscar Wilde, His Life and Confessions — Volume 1Author: Frank HarrisLanguage: English
- Oscar Wilde, His Life and Confessions. Volume 1 (of 2)Author: Frank HarrisLanguage: English
- Oscar Wilde, His Life and Confessions. Volume 2 (of 2)Author: Frank HarrisLanguage: English
- Oscar; Or, The Boy Who Had His Own WayAuthor: Walter AimwellLanguage: English
- Oswald Langdon: or, Pierre and Paul Lanier. A Romance of 1894-1898Author: Hamilton, Levi JacksonLanguage: English
- OthelloAuthor: William ShakespeareLanguage: English
- OthelloAuthor: William ShakespeareLanguage: English
- OthelloAuthor: William ShakespeareLanguage: English
- OthelloAuthor: William ShakespeareLanguage: English
- OthelloAuthor: Wilhelm HauffLanguage: German
- OthelloAuthor: William Shakespeare, Christoph Martin WielandLanguage: German
- OthelloAuthor: William Shakespeare, Paavo Emil CajanderLanguage: Finnish
- OthelloAuthor: William Shakespeare, François GuizotLanguage: French
- Other Main-Travelled RoadsAuthor: Hamlin GarlandLanguage: English
- Other People's Business: The Romantic Career of the Practical Miss DaleAuthor: Harriet L. (Harriet Lummis) SmithLanguage: English
- Other People's MoneyAuthor: Emile GaboriauLanguage: English
- Other Tales and Sketches: (From: "The Doliver Romance and Other Pieces: Tales and Sketches")Author: Nathaniel HawthorneLanguage: English
- Other Things Being EqualAuthor: Emma WolfLanguage: English
- Other Worlds: Their Nature, Possibilities and Habitability in the Light of the Latest DiscoveriesAuthor: Garrett Putman ServissLanguage: English
- Otto of the Silver HandAuthor: Howard PyleLanguage: English
- Oude Egyptische LegendenAuthor: Margaret Alice MurrayLanguage: Dutch
- Oulua soutamassaAuthor: Teuvo PakkalaLanguage: Finnish
- Our American CousinAuthor: Tom TaylorLanguage: English
- Our Boys: Entertaining Stories by Popular AuthorsAuthor: VariousLanguage: English
- Our Casualty, and Other Stories: 1918Author: George A. BirminghamLanguage: English
- Our Catholic Heritage in English Literature of Pre-Conquest DaysAuthor: Emily Henrietta HickeyLanguage: English
- Our Changing ConstitutionAuthor: Charles W. (Charles Wheeler) PiersonLanguage: English
- Our Churches and Chapels: Their Parsons, Priests, & Congregations: Being a Critical and Historical Account of Every Place of Worship in PrestonAuthor: AtticusLanguage: English
- Our Common Insects: A Popular Account of the Insects of Our Fields, Forests, Gardens and HousesAuthor: A. S. (Alpheus Spring) PackardLanguage: English
- Our Day: In the Light of ProphecyAuthor: William Ambrose SpicerLanguage: English