Deiser, Oliver (May 2010). "On the Development of the Notion of a Cardinal Number". History and Philosophy of Logic. 31 (2): 123–143. doi:10.1080/01445340903545904. S2CID171037224.
Deiser, Oliver (May 2010). "On the Development of the Notion of a Cardinal Number". History and Philosophy of Logic. 31 (2): 123–143. doi:10.1080/01445340903545904. S2CID171037224.