This paper generated two comment papers in Geophysics.
My replies to these comments are contained in the following:
J. G. Berryman, ``Reply to
K. Helbig,'' Geophysics 45, 977-982 (1980).
J. G. Berryman, ``Reply to
F. M. Lyakhovitskiy,'' Geophysics 46, 336-339 (1981).