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

Owen, Charles A., Jr. "Pre-1450 Manuscripts of the Canterbury Tales: Relationships and Significance (Part II)." 23 (1988): 95-116.
No evidence suggests that any of the d manuscripts are the product of a group of scribes in a shop. The b manuscript group seems to have been produced after 1450. Three methods of manuscript production can be discerned after careful study. First, exemplars were gathered for specific occasions, resulting in manuscripts like Hengwrt, Harley 7334, Cambridge Dd, Ellesmere, and Cambridge Gg. Second, copies were made of pre-existing manuscripts. Third, a manuscript might be the product of amassing "exemplars made for a previous manuscript" (114).