[en] The study of one-proton transfer reactions induced by a 56 MeV ¹⁶O beam and a 48 MeV ¹²C beam on a ⁶⁴Ni target is described. Since the spectroscopic strength of the single-particle states of ⁶⁵Cu are well established through (³He,d) or (α,t), these one-proton transfers provide a first check of the validity of DWBA calculation applied to the data from reactions induced by heavy projectiles. Two-proton transfer data provided by the (¹⁶O,¹⁴C) transfer reaction performed at 56 MeV ¹⁶O incident energy on ⁶⁴Ni, ⁷⁴Ge and ⁷⁶Ge separated target isotopes are also given. The angular distribution of the first excited levels populated by this (¹⁶O,¹⁴C) reaction exhibits very different behaviour. Diffraction phenomena are present in the case of ⁶⁴Ni target isotopes while two-step processes involving core excitation of the target and/or residual nucleus definitively have to be invoked in order to explain the data on Ge isotope cases. Furthermore it is shown that spectroscopic information can probably be obtained only through a detailed microscopic form factor calculation of the two protons transferred. (Auth.)