The Chaucer Review: An Indexed Bibliography (Vols. 1-30)

Finlayson, John. "The Form of the Middle English Lay." 19 (1985): 352-68.
Few Middle English texts can claim to be lays, works modelled on the Breton lays of Marie de France. Generally, lays are "set in Brittany, concern love, and have a functional magical element" (361), though lays vary substantially between themselves. The similarities between Sir Degare, Le Freine, and Sir Orfeo, particularly in word choice may result from a joint author-translator. Examination of the works claiming to be lays--the Franklin's Tale, Erl of Tolous, Sir Launfal, Emaré, and Sir Gowther--shows that they can be divided into two types, but that the later works modify the form of the lay considerably.

Hanks, D. Thomas, Jr. "Emaré: An Influence on the Man of Law's Tale." 18 (1983): 182-86.
Though scholars have viewed Emaré as only an analogue to the Man of Law's Tale because of the date of the earliest extant manuscript, careful reading of the romance reveals significant plot and verbal parallels. Readers can assume, therefore, that Chaucer must have read a previous version of the story, no longer extant.