Flynt, J. A. The World of Graft. New York, 1901.
—— Notes of an Itinerant Policeman. Boston, 1900.
—— Tramping with Tramps. 1903.
—— tr. German, by du Bois-Raymond. Berlin, 1904.
—— The Powers that Prey.
—— My Life. New York, 1908.
Fourguet. Les faux témoins; Essai de psychologie criminelle. Châlon-sur-Saône, 1901.
Grasserie, R. de la. De la classification des actes criminels. Paris, 1902.
—— De la criminologie des collectives. Paris, 1903.
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