For spinless particles, and in the particular case of ω ω = ( 1 / c , 0 , 0 , − − 1 / c ) , the amplitudes found by the rules of covariant graph techniques, after replacement of variables, are reduced to the amplitudes given by the Weinberg rules in the infinite momentum frame. The dependence on orientation of the light-front plane manifests itself in the dependence of the off-energy-shell Weinberg amplitudes on the variables k → → ⊥ ⊥ i , x i taken separately but not in some particular combinations like the Mandelstam variables s , t .