F. Csáki and S. Benedikt, “BOOll REVIEW - BUCHBESPRECHUNG. Butenin. N. V.: Elements of the Theory of Nonlinear Oscillations. Aizerman, M. A. , Gantmacher, F. R.: Absolute Stability of Regulator Systems. Dean, K. J.: Digital Instruments. Modern Electrical Studies”., Period. Polytech. Elec. Eng., vol. 10, no. 1, pp. 81–83, Jan. 1966.