Try googling Bell Labs computer music and you will get more results. The EMF Institute even has a snippet of a computer singing "Bicycle Built for Two" as well as a nice timeline. A lot of this research was done as part of computer music research. Max Mathews, today hailed as the father of computer music, held the title "Director of Acoustic and Behavioral Research" until 1985 so the work would of been done under him. There's a lot of interesting sounds produced out of these researches at Bell and Princeton and others who set up computer music labs.
Good luck, it's fascinating stuff.
Good luck, it's fascinating stuff.