R.I. 324 On a Model of two Conservation Laws Arising in Magnetohydrodynamics by B.T.hayes and P.G.Lefloch The whole paper is available as a compressed Postscript file by internet procedure FTP anonymous on host barbes.polytechnique.fr ( 129.104.4.100) in the directory pub/RI/1996 under the name hayes_lefloch_324.jan.ps.gz or by Netscape or any other www client via the CMAP www server "http://www.cmap.polytechnique.fr/"