  The proton is formulated as a relativistic system of three constituent quarks
interacting via a zero-range two-body force in the null-plane. The covariance
of the null-plane Faddeev-like equation under kinematical front-form boosts is
discussed. A simplified three-boson model of the nucleon wave-function is
obtained numerically. The proton electric form-factor reproduces the
experimental data for low momentum transfers and qualitatively describes the
asymptotic region.
