"Münzmeister in Warschau." - https://ikmk.smb.museum/object?id=18203668, 28.08.2018
"Brenn, Ephraim (Germ.). Mint-master at Warsaw, 1774-1792. The currency issued under him bears his initials E.B." - Forrer, L. "Biographical Dictionary of Medallists", Bd. 1 (London 1904), S. 276
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