File talk:Giovanni Battista Riccioli.jpg

Source
In case it should help anyone else with their research, I'll just leave some notes about the source of this image here.

The portrait is an engraving by "G. B. Galli" and was featured on page 6 of this Italian library exhibition catalog published in 1998:

http://dm.unife.it/comunicare-matematica/filemat/mostre.htm

http://dm.unife.it/comunicare-matematica/filemat/pdf/Gesuiti.pdf#page=6

I assume that "G. B. Galli" is Giuseppe Galli Bibiena.

As far as I can tell, there are no higher quality copies of this portrait available online.

The original engraving is held at the Biblioteca Comunale Ariostea historical library in Ferrara, Italy.