[en] In the Kobayashi-Maskawa model, the neutron electric dipole moment is a high order effect in the electroweak interactions. We need a perturbative calculation in two steps: generation of CP-violating couplings at the quark level through heavy quark loops, and a perturbative expansion by nearest intermediate states at the bound state level. We examine both aspects for a mechanism proposed by Morel and by Cox, Nanopoulos and Yildiz where CP violation comes from transition quark electric dipole moments. We retain the lowest lying baryon intermediate states 1/2⁺ (56,0⁺) and 1/2^- (70,1^-). For this mechanism we get at most (Dsub(n)/e approximately equal to 10^-34 cm