In this paper some properties of unimodular (or 

 -) and paramount (or 

 -) matrices are discussed. The paper deals with matrices 

 which may be decomposed in a congruence 

 where 

 is a rectangular unimodular- and 

 a diagonal- matrix with constant, positive and real diagonal elements. It is shown that such a decomposition, if at all possible, is essentially unique and a direct algebraic procedure is given which results either in finding the pair of matrices 

 and 

 or in a proof that such decomposition is impossible. Since the admittance matrices of 

 -ports described on pure resistance networks (or RLC networks for positive, real values of the complex frequency) with 

 nodes, or dually the impedance matrices of 

 -ports inscribed into 

 -networks with exactly 

 independent links belong to the Class of 

 matrices the paper defines a method of decomposition of such matrices into the product 

 . The synthesis of the corresponding 

 -port may then be realized by known methods.