[by] I. V. Pyatnitskii. Translated by N. Kaner. [by] L.A. Dorfman. Translated by N. Kemmer. by J. P. Mathieu ; translated by J. Warren Blaker. by J. C. Simon ; Translated by J. Howlett by I.M. Tsidilkovski ; translated by R.S. Wadhwa. by P. Gombbas and D. Kisdi. [Translated by J. Schanda] [by] I. G. Kaplan. Translated by J. Gerratt. by R. Courant. Translated by E. F. McShane.