1. Introduction

In this paper it is shown that the location and direction of a diode
in the interior of a rectangular network can be determined by
measurements of boundary output currents generated by internal current
sources.  The boundary measurements will also be used to determine the
conductors (and conductances) in the network.

2. Preliminaries for all rectangular networks

3. Forward problem without a diode

4. Inverse problem without a diode

5. Preliminaries for a network with a diode

6. Inverse Problem with a Diode

6. Conclusions