John B Friedman (1989)
Peacocks and preachers: analytic technique in Marcus of Orvieto's Liber de moralitatibus, Vatican lat. MS 5935
In: Beasts and Birds of the Middle Ages. The Bestiary and its Legacy, ed. by Willene B. Clark/Meradith T. McMunn. University of Pennsylvania Press, Philadelphia, pp. 176-196.