The non-isentropic steady spatial double-wave equations of an ideal ga
s with an equation of state of the form tau = g(p)A(2) (S) are investi
gated in two cases, omitted previously [1]: when H not equal 0, F-2' =
cF(3)' and when H = 0 with straight level lines. (C) 1997 Elsevier Sc
ience Ltd. All rights reserved.