On: “Inversion of normal incidence seismograms” by A. Bamberger, G. Chavent, Ch. Hemon, and P. Lailly (GEOPHYSICS, May 1982, p. 757–770)

In an early section of their paper, Bamberger et al present analyses which lead them to conclude (p. 759) “This is why we replace Kunetz’s sequential…determination of [Formula: see text] by an iterative but simultaneous determination of all the impedance values [Formula: see text], k = 2, …, 300.” Unfortunately, their analysis leading to this conclusion is, as we demonstrate below, incorrect. In fact, the correct analyses can lead to a rather surprising conclusion, due in part to an interesting experiment performed by the authors that is summarized in their Figure 2.