If like me you have accumulated a massive list of references in Word 2011's built in reference manager, and don't want to lose them on the way to 2016, this should help.
For 2011 your old sources.xml is located at:
Macintosh HD/Users/*USER*/Library/Application Support/Microsoft/Office
I found the location of the new sources.xml at:
Macintosh HD/Users/*USER*/Library/Containers/com.microsoft.Word/Data/Library/Application Support/Microsoft/Office
Just copy and paste the old one to the new location, replace the one that is already there, and you're set! Note *USER* is your user name.
For 2011 your old sources.xml is located at:
Macintosh HD/Users/*USER*/Library/Application Support/Microsoft/Office
I found the location of the new sources.xml at:
Macintosh HD/Users/*USER*/Library/Containers/com.microsoft.Word/Data/Library/Application Support/Microsoft/Office
Just copy and paste the old one to the new location, replace the one that is already there, and you're set! Note *USER* is your user name.