Are diaries art? Each of these books treats the material object of the diary as a form of visual art.

Beyond Words: 200 Years of Illustrated Diaries by Susan Snyder (Bancroft Library, 2011)

Un Journal A Soi: Histoire d’une Pratique, Philippe Lejeune and Catherine Bogaert (Textuel, 2003) 

Sophie du Pont: A Young Lady in America, Sketches, Diaries & Letters, 1823-1833, Betty-Bright Low and Jacqueline Hinsley (Harry N. Abrams Pub, 1987)