J. W. M. will find this question discussed at length in the
_Dictionnaire de Bayle_, art. "Lamech," and more briefly in _Pol.
Synopsis Criticorum_, Gen. iv. 23.
The subject has been engraved by Lasinio in his _Pitture a fresco del
Campo Santo di Pisa_ (tom. xvii.), after the original fresco by
Buonamico Buffalmacco, whose name is so familiar to readers of the
_Decameron_.