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The following is an alphabetical list of authors, other than Sherlock Holmes's creator Sir Arthur Conan Doyle, who have authored Holmes stories:
Boris Akunin: "Jade Rosary Beads" (crossover with Erast Fandorin)
Val Andrews
Isaac Asimov
Poul Anderson: "Time Patrol", where the main character meets Sherlock Holmes and Dr. Watson during time travels
John Kendrick Bangs
Stephen Baxter: "The Adventure of the Intertial Adjustor" (Holmes and Watson meet H.G. Wells), The Mammoth Book of New Sherlock Holmes Adventures, 1997
Peter S. Beagle: "Mr. Sigerson", Sherlock Holmes: The Hidden Years, 2004
Lloyd Biggle
David Blackburn
Anthony Boucher
Mark Bourne
Rhys Bowen: "The Case of the Lugubrious Manservant", Sherlock Holmes: The Hidden Years, 2004
Richard Boyer
Clive Brooks
Carole Bugge
Caleb Carr
John Dickson Carr
Michael Chabon: The Final Solution features an unnamed elderly Sherlock Holmes
Ian Charnock
Ronan Coghlan Sherlock Holmes and the Heir of Albion
Michael Collins: "Cross of Gold", Sherlock Holmes: The Hidden Years, 2004
Paul Cornell: "The Deer Stalker"
Jon Courtenay Grimwood: "The Spy's Retirement"
Mitch Cullin: "A Slight Trick of the Mind"
David Stuart Davies
Barry Day
F. P. Cillié: "The Adventure of the Green Empress", The Further Adventures of Sherlock Holmes, 1985.
August Derleth, whose Solar Pons series are reverent pastiches.
Colin Dexter
Michael Dibdin
Carole Nelson Douglas (books about Irene Adler)
Adrian Conan Doyle (Conan Doyle's son, and former holder of his estate)
Loren D. Estleman
Philip José Farmer (one book - The Adventure of the Peerless Peer, in which Holmes teams up with Tarzan.)
Quinn Fawcett
Christopher Fowler "The Lady Downstairs"
Neil Gaiman: "A Study in Emerald", in the multi-author collection Shadows Over Baker Street, won the 2004 Hugo for Best Short Story.
Arnould Galopin (crossover with Allan Dickson)
John Gardner (books about Professor Moriarty)
David Gerrold
Denis Green
Dominic Green "The Adventure of the Lost World"
L. B. Greenwood: Novels, and the short story "The Case of the Last Battle", The Mammoth Book of New Sherlock Holmes Adventures, 1997
Claire Griffen: "The Case of the Incumbent Invalid", The Mammoth Book of New Sherlock Holmes Adventures, 1997
Kelly Hale
Edward B. Hanna
Michael Hardwick
Edward D. Hoch: "The Adventure of Vittoria the Circus Belle", The Mammoth Book of New Sherlock Holmes Adventures, 1997
Michael P. Hodel: Enter the Lion, Dutton Adult, 1980, ISBN 0-8015-5286-9
Sidney Hosier
Stephen King: "The Doctor's Case", in which Watson solves a case before Holmes.
Laurie R. King: The Mary Russell series of novels set in Holmes' later life (ongoing as of February 2009).
Ronald A. Knox: "The Adventure of the First-Class Carriage", The Further Adventures of Sherlock Holmes, 1985.
Michael Kurland (books about Professor Moriarty), and the short story "Reichenbach", Sherlock Holmes: The Hidden Years, 2004
Andy Lane
Maurice Leblanc (crossover with Arsène Lupin)
Alexis Lecaye
James Lowder
F. Gwynplaine MacIntyre (“The Enigma of the Warwickshire Vortex” (1997) and “The Adventure of Exham Priory” (2003))
Vonda N. McIntyre
W. R. Duncan Macmillan: "The Adventure of the Trained Cormorant", The Further Adventures of Sherlock Holmes, 1985.
Rafael Marín: Elemental, querido Chaplin, (2005, ISBN 844507542X , is presented as a unpublished manuscript in which Charles Chaplin tells how, as a London poor child, he helped Sherlock Holmes in an adventure against Fu Manchu.
Rodolfo Martínez
Xavier Mauméjean
Nicholas Meyer: Three novels — The Seven-Per-Cent Solution (1972), The West End Horror (1976) and The Canary Trainer (1993)
Larry Millett
Kim Newman A Shambles in Belgravia
Robert Newman
Béatrice Nicodème
Jamyang Norbu: The Mandala of Sherlock Holmes
John North
Sam North: The Curse of the Nibelung - A Sherlock Holmes Mystery
Stuart Palmer: The Adventure of the Marked Man, The Further Adventures of Sherlock Holmes, 1985.
Bill Paxton
Anne Perry
René Réouven
Mike Resnick
Ted Riccardi: The collection The Oriental Casebook of Sherlock Holmes
Kel Richards
Barrie Roberts
Ralph Roberts
S. C. Roberts: "The Adventure of the Megatherium Thefts", The Further Adventures of Sherlock Holmes, 1985.
Kristine Kathryn Rusch
Fred Saberhagen
Autumn Sabol : Elementary, My Dear, 2004
Robert Saffron
Siyaram Saran: The Boer War Mystery: Sherlock Holmes and Dr.Watson meet Sir Arthur Conan Doyle, who was there as a Medical Doctor and an Indian Barrister M.K.Gandhi (Mahatma Gandhi) in South Africa, who was then practising law there and who inspired Holmes to take up Bee-Keeping after his retirement.
Dorothy L. Sayers
Jay Sheckley : "Vittoria the Circus Belle", "Confidential Casebook of Sherlock Holmes" which Publishers Weekly called "The best of an