Detail from article on Fitzgerald Music Company, photograph of officers and staff, including John E. Yuncker.

Source: "'It Can Be Done' as Trade Slogan: Fitzgerald Music Company, of Los Angeles, Proves that Summer Months May Be the Greatest of the Whole Year," Presto: The American Music Trade Weekly, August 25, 1923; online archives, The International Arcade Museum (http://presto.arcade-museum.com/PRESTO-1923-1935/ : downloaded 11 March 2015), page 6.