  Scattering lengths for d-d, n-$^3$He and p-$^3$H systems are computed via
Cluster Reduction Method for Yakubovsky equations in configuration space taking
into account Coulomb interaction between protons. MT I-III potential model was
used to describe the nucleon-nucleon interaction. Results of calculations are
in a good agreement with existing experimental data and results of calculations
of other authors.
