found: Warum lügst du, Chérie?, c1937:t.p. (Leonhard K. Märker)
found: Deutsche Nationalbibliothek, via VIAF, viewed Sept. 30, 2021(Märker, Leonhard K., born 1911 (variously 1910, 1912), Vienna, died 1993, New York; variant access points: Kuhmaerker, Leonhard; Kuhmärker, Leonhard; Maerker, Leonhard K.; Marco, Leonard; Marker, Leonard K.; Märker, Leonhard; Cowmar, Hardy (pseudonym); Kuhmärker, Leonhard Karl (real name); composer) - http://www.viaf.org/processed/DNB%7C138155089
found: Oesterreichisches Musiklexikon Online WWW site, viewed Sept. 30, 2021(Märker (Marker, also Kuhmärker), Leonhard (Leonard) Karl; born March 28, 1910 [Lang gives August 1, 1911, Vienna] Brody/Galizien (today), died 1993, New York; composer; emigrated to the USA) - https://www.musiklexikon.ac.at/ml/musik_M/Maerker_Leonhard.xml
found: U.S., Social Security Applications and Claims Index, 1936-2007, via Ancestry, viewed Sept. 30, 2021(Leonard K. Marker; born August 1, 1911, died January 26, 1993; male)
found: New York, U.S., Arriving Passenger and Crew Lists (including Castle Garden and Ellis Island), 1820-1957, via Ancestry, viewed Sept. 30, 2021(Leon Kuhmarker; born abt. 1911, Brody, Poland; last known residence: Marseille, France; departure port: Casablanca, Morocco; arrival date: June 25, 1942, arrival port: New York, New York, final destination: Indiana; gender: male, ethnicity/nationality: Jewish; marital status: single; age: 31)
found: U.S., World War II Draft Cards Young Men, 1940-1947, via Ancestry, viewed Sept. 30, 2021(Leonard Kuhmarker; born January 8, 1910, Brody, Poland; registration date: July 28, 1942, New York City, New York; white; age: 32)