It is noteworthy that Frege died as late as 1925 since we tend to think of him as predating his contemporaries, Russell and Husserl. In fact, Frege's reputation has undergone some rather wild swings over the years. Early on he was undervalued, a chapter in Russell. These days, after Wittgenstein's philosophical hara kiri and the detection of multiple problems with Russell's grand attempt to synthesize symbolic logic, set theory and empiricism, Frege may be a bit overvalued. Nevertheless, his writings on logical grammar and the foundations of arithmetic deserve a permanent place in the philosophical syllabus.

Schriften zur Logic und Sprachphilosophie aus dem Nachlass

Frege and Pünjer on Existence

Die Grundlagen der Arithmetik

Funktion - Begriff - Bedeutung

Object Reference and Truth-Value Reference in Über  Sinn und Bedeutung

Begriffschrift