The sinh-Gordon defect matrix generalized for n defects
  In this paper we obtain a general expression for the n-defect matrix for the sinh-Gordon model. This in turn generate the general B\"acklund transformations (BT) for a system with $n$ type-I defects, through a gauge transformation. 
N.I. Spano, A.L. Retore, J.F. Gomes, A.R. Aguirre and A.H. Zimerman
nlin.SI