Electrostatic potential of a uniformly charged disk through Green's theorem

All existing derivations of the electrostatic potential of a uniformly charged disk are technically rather involved. In an old and now almost forgotten publication, Duffin and McWhirter proposed a method for calculating the electrostatic potentials of planar bodies by a skillful application of Green's theorem. It is shown that this method significantly simplifies the problem of calculating the electrostatic potential of a uniformly charged disk and makes it an almost trivial task.