  Let F be a finite extension of Qp and G be GL(2,F). When V is the tensor
product of three admissible, irreducible, finite dimensional representations of
G, the space of G-invariant linear forms has dimension at most one. When a non
zero linear form exists, one wants to find an element of V which is not in its
kernel: this is a test vector. Gross and Prasad found explicit test vectors for
some triple of representations. In this paper, others are found, and they
almost complete the case when the conductor of each representation is at most
1.
