In their recent paper, Drs. Ghosh and Kumar considered the relevant problem of convergence of the power series expansions of traveltime and offset as functions of horizontal slowness, claiming that these are nowhere analytical functions. Based on this claim, they conclude that the commonly used series expansion of traveltime and traveltime squared as a function of offset is also nowhere analytic, namely that the radius of convergence is zero. This contradicts previous results of Goldin (1986) and Tygel (1994), who have shown that these power series have some minimum, model-dependent, nonempty convergence regions. In what follows, we shall briefly state the problem and show that the arguments and the claim made by Drs. Ghosh and Kumar are wrong.

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