1428 THE BELL SYSTEM TECHNICAL JOURNAL, NOVEMBER 1957 



2. John G. Truxal, Automatic Feedback Control System Synthesis, McGraw- 



Hill Book Co. Inc. New York, 1955. 



3. R. Courant and D. Hilbert, Methods of Mathematical Physics, Inter.science 



Publishers, Inc. New York, 1953. 



4. W. R. Bennett, Steadv-state Transmission Through Networks Containing 



Periodically Operated Switches, I.R.E. Trans., PGCT.2, No. 1, pp. 17 22, 

 March, 1955. 



5. T. R. Bashkow, The A-matrix, New Network Description, to be published in 



I.R.E. Trans., PGCT.4, No. 3, 1957. 



