  From the computation of three-point singlet correlators in the two-matrix
model, we obtain an explicit expression for the macroscopic three-loop
amplitudes having boundary lengths $\ell_{i}$ $(i = 1\sim 3)$ in the case of
the unitary series $(p,q)= (m+1,m)$ coupled to two-dimensional gravity. The sum
appearing in this expression is found to conform to the structure of the CFT
fusion rules while the summand factorizes through a product of three modified
Bessel functions. We briefly discuss a possible generalization of these
features to macroscopic $n$-loop amplitudes.
