Paul Abelson (1915), “Mephistopheles”, in English-Yiddish Encyclopedic Dictionary, New York: The Jewish Press, page 862
Justus van de Kamp et al., “מעפֿיסטאָ” in Jiddisch-Nederlands Woordenboek [Yiddish-Dutch Dictionary], Amsterdam: Stichting Jiddische Lexicografie, 1987-present (ongoing). [1].