Books about Triangles (Interpersonal relations) -- Fiction (sorted alphabetically)
- Claverings Anthony Trollope
- closed door John Fleming Wilson and Mary Ashe Miller
- Coeur de femme (French) Paul Bourget
- Colin E. F. Benson
- Confounding of Camelia Anne Douglas Sedgwick
- Crater Robert Gore Browne
- Dark Tower Phyllis Bottome
- Dead Letter: An American Romance Metta Victoria Fuller Victor
- Delilah of the Snows Harold Bindloss
- Devotee: An Episode in the Life of a Butterfly Mary Cholmondeley
- Divine Lady: A Romance of Nelson and Emma Hamilton L. Adams Beck
- Dodo: A Detail of the Day. Volumes 1 and 2 E. F. Benson
- Donna Teresa Frances Mary Peard
- Dust Flower Basil King
- East Angels: A Novel Constance Fenimore Woolson
- Ethan Frome Edith Wharton
- Ethan Frome Edith Wharton
- Far from the Madding Crowd Thomas Hardy
- Far from the Madding Crowd Thomas Hardy
- Far from the Madding Crowd Thomas Hardy
- Felix Holt, the Radical George Eliot
- Folly Corner Mrs. Henry Dudeney
- Footsteps of Fate Louis Couperus
- Friendship and Folly: A Novel Maria Louise Pool
- Fruit of the Tree Edith Wharton