From Lagrange to Frege
functions and expressions
Part I of Frege's Grundgesetze is devoted to the "exposition [Darlegung]" of his formal system.
Benis-Sinaceur, H. , Panza, M. , Sandu, P.-G. (2015). From Lagrange to Frege: functions and expressions, in Functions and generality of logic, Dordrecht, Springer, pp. 59-95.
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