# Origin of Hecke operators

What is the original paper in which Erich Hecke had first introduced the Hecke operators?

• To be fair, Mordell had used "Hecke operators" in proving the weak multiplicativity of Ramanujan's tau-function, that is, of the Fourier coefficients of the holomorphic cuspform of weight 12. – paul garrett Jun 3 '19 at 17:46

## 1 Answer

Über Modulfunktionen und die Dirichletschen Reihen mit Eulerscher Produktentwicklung. I, Math. Ann. 114 (1937), 1-28; II, ibid., 316-351. These two papers are available here and here.