879392.fig.001a
(a)
879392.fig.001b
(b)
879392.fig.001c
(c)
Figure 1: (a) Equifrequency surface diagram for an isotropic medium ( ). (b) Equifrequency surface diagram for an anisotropic medium ( ). (c) Equifrequency surface diagram for an indefinite medium (hyperbolic) with ( , ).