Addendum
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Ioannis M. Besieris, Professor Emeritus, Th Bradley ECE Department , Virginia Tech
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November 9, 2025

An all-space analytical solution for the potential field due to a uniformly charged square plate of size L has been derived in the following article:​
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​ O. Ciftja, “Electrostatic potential of a uniformly charged square plate at an arbitrary point in space,” Phys. Scripta 95, 095802 (2020).

This solution coincides with that found using Mathematica provided the change b -> a ->2 L is made in the latter.​
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