It is shown that the Jacobian determinant being nonzero for all values of its variables is both necessary and sufficient for the uniqueness of solutions of a wide class of networks. These networks may contain negative-resistance ...

Homeomorphism of matrix equations of the form f(x)=g(x)+Hx=y, where g is nondiagonal, is studied. It is shown that contrary to common belief, from a practical point of view, the condition that the Jacobian determinant is ...