For original paper see Deutsch et al., Plasma Physics vol.28, p.1823 (1986). Deutsch et al. presented two sets of arguments to support the inclusion of a new term in the Kirchhoff law for the equivalent circuit of plasma focus devices. This was done on account of the difficulty they found when trying to computer simulate the measured values of the accelerator voltage and current time derivative, using reasonable values of the gun plasma inductance and resistance in the equivalent circuit for the device. Bruzzone and Kelly comment that they feel the arguments presented by Deutsch et al. are not sufficient to justify the addition of an extra term in the equation of a plasma focus device related to the described shock wave structure.