Gerould, D.C. (1992). Guillotine, Its Legend and Lore. Blast Books. p. 78. ISBN978-0-922233-02-1. Consultado el 16 de septiembre de 2018. (requiere registro). «The job of executioner had become part-time. Henri Desfourneaux's two assistants also worked as a butcher and a hairdresser — fitting sidelines to their decapitating functions. The last guillotine operator, Marcel Chevalier, incumbent from ...»
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Clarke, P.; Hardy, L.; Williams, A. (2008). Executioners. Book Sales. pp. 374-380. ISBN978-0-7088-0366-0. Consultado el 16 de septiembre de 2018.