FRAENKEL, Abraham. Der Begriff “definit” und die Unabhängigkeit des Auswahlaxioms.
Berlin: Preussischen Akademie, 1922. First edition, author's presentation offprint issue.

An excellent copy of this milestone in mathematical logic (van Heijenoort: From Frege to Gödel, 1922b). In this article, "the first work on models of set theory" (Gregory H. Moore), Fraenkel gave the first proof of the independence of the axiom of choice. "In an important paper [ibid] Fraenkel clarified the notion of 'definiteness' in Zermelo's seperation axiom by restricting the function involved to a finite number of logical operations ... This was one of his modifications to Zermelo's system which has led his name to be attached to it, and the acronym 'ZF'." (Grattan-Guinness: The Search for Mathematical Roots 1870-1940, p.478).

Offprint from: Sitzungsberichte der Preussischen Akademie der Wissenschaften, XXI, pp. 253-257. Large 8vo: 254 x 184 mm. Original printed wrappers with 'Überreicht vom Verfasser' printed on the front wrapper. Slight vertical crease from having been folded, and some very light smudging to front wrapper, otherwise fine. Scarce.