by E. W. Golding and F. C. Widdis. by A. R. Penfold and J. L. Willis. by J. V. Dacie and S. M. Lewis. by N. F. Mott and E. A. Davis. by R. N. Haszeldine and A. G. Sharpe. by J. Laing and R. T. Rolfe. by J. M. Camp and C. B. Francis. W. Goldring and H. Chasis. by D.R. Cox and P.A.W. Lewis.