Books about Triangles (Interpersonal relations) -- Fiction (sorted alphabetically)
- Jocelyn John Galsworthy
- John Marchmont's Legacy, Volume 1 (of 3) M. E. Braddon
- John Marchmont's Legacy, Volume 2 (of 3) M. E. Braddon
- John Marchmont's Legacy, Volume 3 (of 3) M. E. Braddon
- John Marchmont's Legacy, Volumes 1-3 M. E. Braddon
- Judgment House Gilbert Parker
- Juha (Finnish) Juhani Aho
- Kenny Leona Dalrymple
- Kit Musgrave's Luck Harold Bindloss
- Lead of Honour Norval Richardson
- letra escarlata (Spanish) Nathaniel Hawthorne
- Little Lady of the Big House Jack London
- Lost Tribes of Venus Erik Fennel
- Love in Excess; or, the Fatal Enquiry Eliza Fowler Haywood
- luckless trapper; or, The haunted hunter William R. Eyster
- Mademoiselle de Maupin (French) Théophile Gautier
- Mäenkylän maitomies: Romaani (Finnish) Eduard Vilde
- Magic H. De Vere Stacpoole
- Mal Moulée: A Novel Ella Wheeler Wilcox
- Marriage of William Durrant Ray Cummings
- Mary Barton Elizabeth Cleghorn Gaskell
- Mary Wollaston Henry Kitchell Webster
- Master of Appleby Francis Lynde
- Masters of the Wheat-Lands Harold Bindloss
- Matchmaker Charles L. Fontenay