Ref.

Noun

 * 1)   (title)
 * 1)   (title)

Usage notes
This is the customary abbreviation of this term as used in legal citation. See, e.g., The Bluebook: A Uniform System of Citation, Nineteenth Edition (2010), "Case Names and Institutional Authors in Citations", Table T6, p. 430-431; "Judges and Officials", Table T11, p. 443.