We discuss the perturbative approachà la Dyson to a quantum field theory with nonlocal self-interaction : φ ⋆ · · · ⋆ φ :, according to Doplicher, Fredenhagen and Roberts (DFR). In particular, we show that the Wick reduction of non locally time-ordered products of Wick monomials can be performed as usual, and we discuss a very simple Dyson diagram.Dedicated to Jacques Bros on the occasion of his 70 th birthday.