Here’s the first link.  It’s to Mr John Fletcher’s page for the Vivaldi Gloria.  He has included most of the current editions of the piece. The last is the one we are using.  

Antonio Vivaldi Gloria 

Or you could listen online to the piece on Cyberbase

Cyberbase doesn’t let you download the files.

Antonio Vivaldi

Some YouTube offerings:

The National Chamber Orchestra of Armenia and the National Choir of Armenia 

Choir of King's College, Cambridge - Gloria(Vivaldi).wmv - YouTube

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