Note on obliquely propagating nonlinear Alfven wave

In their recent paper on obliquely propagating nonlinear Alfven wave, Mio et al. inferred that Kakutani and Ono treated a particular nonlinear wave and did not study nonlinear phenomena resulting from increasing amplitude of the linear Alfven wave. It is shown in this paper that the analysis due to Kakutani and Ono is more general than that by Mio et al. and includes the latter as a special case of small amplitude. (author)