On the critical values of Hecke L-functions for imaginary quadratic fields. Ralph Greenberg — 1985 Inventiones mathematicae
p-adic L-functions and p-adic periods of modular forms. Glenn Stevens; Ralph Greenberg — 1993 Inventiones mathematicae
On the Behaviour of p-Adic L-Functions at s= 0. Bruce Ferrero; Ralph Greenberg Inventiones mathematicae