Request biographical information on professor Virgilio Cassio.  He was
the director of the study of the mosaic of the Vatican.  He lived in
Rome, was employed by the Vatican.  He was born in 1914 and passed
away this past year.  Request biographical information and listing of
works he was involved in.  All information needs to be in English.

I purchased a glass mosaic by Virgilio Cassio in Rome in 1971 and was
told at that time that he was the Director of the Vatican School of
Mosaics. Perhaps you will have some luck by searching for information
on this organization.