[en] The behaviour of transverse nucleon flow is studied in heavy-ion collisions below 100 MeV per nucleon. In connection with recent experiments, a theoretical analysis of the flow inversion is made within the Landau-Vlasov semi-classical approach. Comparisons between theoretical results and experimental data are performed taking into account the experimental constraints. The sensitivity of the flow observables on the nuclear matter properties are discussed, underlying the role of non-locality effects. (author) 10 refs., 5 figs., 2 tabs