Professor Edward DR Wright from the University of South Florida pointed to the Warsaw version of La Sforziada (1490) as the potential source of La Bella Principessa. This was confirmed by Prof. Martin Kemp and Dr. Pascal Cotte in situ in Warsaw in my presence.
The provenance of the portrait from this volume has poignant consequences because it may allow us to reconstruct the history of Principessa before and, especially, after the excision from this illuminated old print. Although the history of the volume is well-documented, what happened after the excision, remains to be further researched.
Who took La Bella Principessa out of Sforziad, when, for what purpose? What happened to this portrait later until it reemerged in the late 20th century? Who in the 19th century added the uniquely decorated frame to her, when, and in what circumstances? What did this portrait mean to him or her? These are major questions I have been occupying myself with for a longer time.