Named in daughter Handel's marriage record.

Handel's marriage was recorded in Loslau. JRI-Poland records the death of Mendel Koslowsky of Loslau in 1848 at the age of 70 years, so he was born 1777-78 and would have been aged about 38 years when Handel was born in 1815; this could be her father.

Mendel is also mentioned in JRI-Poland records as the father of Simon (married 1844 aged 25 years so born 1818-19) and Babette (married 1843 aged 21 years so born 1821-22). Following Mendel's death in 1848 Simon, Babette and Handel Opfer geb. Koslowsky named their next-born sons Emanuel. This would be consistent with Mendel being the father of Simon, Babette and Handel.