"Clip and Paste (For Newspaper and Program Convenience)". The Moving Picture World. May 7, 1921. p. 46. Retrieved November 24, 2024. "Bridgetta Clark, who plays the important role of the mother of Julio in "The Four Horsemen of the Apocalypse," spent a number of years studying for grand opera. Just as she was ready to make her debut in New York an operation on her throat was found to be necessary and after her recovery it was discovered that she could not sing a single note."
"United States Social Security Death Index," database, FamilySearch (https://familysearch.org/ark:/61903/1:1:JGW6-TPK : 11 January 2021), Ruth Lobanoff, Oct 1980; citing U.S. Social Security Administration, Death Master File, database (Alexandria, Virginia: National Technical Information Service, ongoing).
"California, County Birth and Death Records, 1800-1994", FamilySearch (https://www.familysearch.org/ark:/61903/1:1:QPCG-MYC6 : Sat Mar 09 01:39:00 UTC 2024), Entry for Bridgetta Pavlovna Lobanoff and Paul Earl Lobanoff, 5 November 1928.
Schallert, Edwin (June 28, 1922). "Playdom: New Art Theater; Writers' Club to Have Own Center of Drama; Returns From Study". The Los Angeles Times. Pt. II, p. 11. Retrieved November 24, 2024.
