compute the reduction modulo p of certain two-dimensional crystalline representations of small
slope, and give applications to modular forms. … We now summarize what we need to know
about the p-adic and mod p Langlands correspondence for GL2(Qp) here (although we do not
go into the details of extension classes, an important subtlety which we will not need here, and
we shall only discuss the case of crystalline p-adic representations; much is now known in …