Transcripts of Interviews Conducted by Ruby Mercer Concerning Reminiscences of Edward Johnson, Some for "Opera Time."
Ruby Mercer's Notebook Containing Research Notes and Interviews with Family Members, Friends in Guelph, and Colleagues, Concerning Edward Johnson
Edward Johnson Music Foundation History, Reports, Minutes, Etc.; Speeches by Ruby Mercer for the Guild, 1970, and Guelph Spring Festival, 1974