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.