editors, H.A. Cerdeira and S.O. Lundqvist. editors, F.H. Schroder and H.J. de Voogt. editors, D.H. Sharp and T.F. West. editors, R.F. Stebbings and F.B. Dunning. editors, R.J. Kohel and C.F. Lewis. editors, C. Steffen and H. Ludwig. editors, D.C. Fries and B. Zeitnitz. editors, D.F. Mettrick and S.S. Desser. editors, H.P. Weber and W. L鑥thy. editors, J.E. Strutt and J.R. Nicholls.