Quasi-elastic deuteron break-up reactions pd → pp( n) and pd → pn( p) have been studied in complete kinematics at 1 GeV. Two outgoing nucleons were detected in coincidence by means of a two-arm spectrometer. After a correction to the impulse approximation for double scattering and Δ-excitation effects, a good agreement with data is found using a momentum distribution of nucleons in the deuteron computed from nucleon-nucleon potentials. This good agreement is obtained up to 0.5 GeV/ c.