Ruhlmann, William James (1991). Chicago Group Portrait (Box Set)(CD booklet archived online) (Media notes). New York City: Columbia Records. p. 7. Archived from the original on February 13, 2016. Retrieved January 29, 2016.
Ruhlmann, William James (1991). Chicago Group Portrait (Box Set)(CD booklet archived online) (Media notes). New York City: Columbia Records. p. 7. Archived from the original on February 13, 2016. Retrieved January 29, 2016.