The late Lodewijk Jozef (Louk) Engels (d. 217), emeritus professor of medieval Latin at the University of Groningen from 1972 till 1994, has published on Paul Diacre and on many other texts, including the Sermones of Peter Abelard. He has been rector magnificus of his alma mater from 1981 till 1984, and again from 1988 till 1991. Professor Engels was a great supporter of the critical edition, a particular métier which he has taught with enthusiasm to his students.