Non-diagonal solutions of the reflection equation for the trigonometric   $A^{(1)}_{n-1}$ vertex model
  We obtain a class of non-diagonal solutions of the reflection equation for the trigonometric $A^{(1)}_{n-1}$ vertex model. The solutions can be expressed in terms of intertwinner matrix and its inverse, which intertwine two trigonometric R-matrices. In addition to a {\it discrete} (positive integer) parameter $l$, $1\leq l\leq n$, the solution contains $n+2$ {\it continuous} boundary parameters. 
Wen-Li Yang and Yao-Zhong Zhang