Kremer, Michael (1985), "Frege's theory of number and the distinction between function and object", Philosophical Studies, 47 (3): 313–323, doi:10.1007/BF00355206, MR0788101.
Kremer, Michael (1985), "Frege's theory of number and the distinction between function and object", Philosophical Studies, 47 (3): 313–323, doi:10.1007/BF00355206, MR0788101.