(law) A text that is sufficiently well received in its field that it may overcome a hearsay objection and be admitted into evidence in a court of law.

A Treatise of Human Nature: Being an Attempt to Introduce the Experimental Method of Reasoning into Moral Subjects is a book by Scottish philosopher David Hume, considered by many to be Hume's most important work and one of the most influential works in the history of philosophy.

The Magical Treatise of Solomon, also known as the Hygromanteia or Solomonikê, is a collection of late Byzantine-era grimoires written in medieval Greek.

a two-volume treatise on electromagnetism written by James Clerk Maxwell in 1873.

a medieval instruction manual on the astrolabe by Geoffrey Chaucer.

A Treatise on Probability, published by John Maynard Keynes in 1921, provides a much more general logic of uncertainty than the more familiar and straightforward 'classical' theories of probability.