  Perturbing the Seiberg-Witten curves for N=2 U(N_c) and SU(N_c) super
Yang-Mills theory with N_f<N_c flavours with a mass term for the adjoint field
completely lifts the quantum vacuum degeneracy. The generated N=1 effective
superpotential can be obtained from the factorization formulae of
Seiberg-Witten curves with matter. We show that the Affleck-Dine-Seiberg
superpotential emerges. Moreover it appears additive with respect to the
classical superpotential for the meson superfields, as expected from the
Intriligator-Leigh-Seiberg linearity principle.
