  A recently developed three-dimensional approach (without partial-wave
decomposition) is considered to investigate solutions of Faddeev-Yakubovsky
integral equations in momentum space for three- and four-body bound states,
with the inclusion of three-body forces. In the calculations of the binding
energies, spin-dependent nucleon-nucleon (NN) potential models (named, S$_{3}$,
MT-I/III, YS-type and P$_{5.5}$GL) are considered along with the scalar
two-meson exchange three-body potential. Good agreement of the presently
reported results with the ones obtained by other techniques are obtained,
demonstrating the advantage of an approach in which the formalism is much more
simplified and easy to manage for direct computation.

Nuclear Theory