edited by A. van der Laan and A.A. Winters. edited by R.P. van de Riet and W. Litwin. edited by H. van Lelyveld and B.C.J. Zoeteman. edited by Harvey Abramson and M.H. Rogers. edited by P. Morgan and B.H. Baker. edited by P.H. van Knippenberg and C.W. Hilbers. edited by B. P. Straughan and S. Walker. edited by A. Bensoussan and J. L. Lions. edited by E. R. Sears and L. M. S. Sears. edited by J. W. S. Hearle and R. H. Peters.