M

McCAIGH (first name unknown, aka "The Iron Man"): The Riddle of the Onyx Hand, The Washington Square Enigma, others
—from Harry Stephen Keeler's Sing Sing Nights

MacCOMEROU, Adam: Homicidal Psychopathology: Selected Case Histories in the Problems of Homicidal Psychopathology, Together with a Brief Inquiry into Certain Aspects of Aberrant and Divided Personality Among Men of Superior Mentality, by Adam MacComerou, A.B., Ph.D., Litt.D. (causa honoris, Chicago), Sc.D. (Yale), LL.D. (Swarthmore, Columbia, McGill), Lowell Professor of Psychology at Harvard 

—from Joel Townsley Rogers's The Red Right Hand

McFADDEN, Wellesley: French Curve ("An architect on vacation in Europe falls under the sway of a malevolent French design student")

—from the Gary Walkow film Crashing

McFLY, George: A Match Made in Space
—from the Robert Zemekis film Back to the Future

McMURRAY, Richard: The Trouble With Dick ("A science fiction writer struggles to complete his first novel and maintain his sanity while sharing his house with three very different women")

—from the Gary Walkow film Crashing

MALCO, Jacob: The Mellowcraft Papers
—from the Netflix series Easy (season 2, episode 5)

MALLEON, Grand Master: The Lineages and Histories of the Great Houses of the Seven Kingdoms, With Descriptions of Many High Lords and Noble Ladies and Their Children
—from George R. R. Martin's A Game of Thrones

MANGROVE, Reginald: Hell Is Other People
—from Jonathan Ames's Wake Up, Sir!

MANIPULATE: Stone Cold Bummer

—from 30 Rock (season 4, ep. 21)

MAREN, Robert Mosley: The Mellowcraft Papers
—from Ambrose Bierce's "Isle of Pines"

MARK, John James: The Case of the Missing Tin-Opener
—from Josephine Tey's Daughter of Time

MARRIOT, Solange: Rien du tout, ou la conséquence
—from Stanislaw Lem's A Perfect Vacuum

MARVIN, Dr. Leo: Baby Steps
—from Frank Oz's What About Bob?

MARWYN, Maester: Book of Lost Books
—from George R. R. Martin's A Feast for Crows

MARZENTZ, Hugo: Are Snakes Necessary
—from Preston Sturges's The Lady Eve

MATURIN, Stephen: Diseases of Seamen
—from Patrick O'Brian's Clarissa Oakes, et al.

MAYHEW, W.P.: Nebuchadnezzer
—from the Coen Brothers film Barton Fink

MEADOWS, Harold: The Secret of Making Love
—from the Harold Lloyd film Girl Shy

MEARS, Benjamin: Air Dance

—from Stephen King's ’Salem's Lot

MEEKER, Ralph Warden: Obstinate Dust
—from Jonathan Lethem's Chronic City

MERRILL, Simon: Sexplosion
—from Stanislaw Lem's A Perfect Vacuum

"A MINOR NOVELIST": The Sores
—from Harry Mathews's The Conversions

MLATJE, Kuno: Odysseus of Ithaca
—from Stanislaw Lem's A Perfect Vacuum

MONK:
Ashes to Ashes
Dust to Dust
—from Abraham Rodriguez's South by South Bronx

MONTSTUART, Logan:

Any Human Heart: The Intimate Journals of Logan Montstuart
The Cosmopolitans
The Girl Factory
The Mind's Imaginings
This Is Not an Exit: Essays on Art and Literature
The Villa by the Lake

—from William Boyd's Any Human Heart

MORGAN, Eunice Eliot: Ramba of Macedon ("a historical novel about a female gladiator...which was a bestseller in 1936")
—from Kurt Vonnegut's God Bless You, Mr. Rosewater

MORRISON, Kirk (aka Gideon Starorzewski, "King Mob"): Dis, The Killing Moon
—from Grant Morrison's The Invisibles

MORTON, Sarah: Dorwell Wears a Kilt
—from the François Ozon film Swimming Pool