References

1. American Standard Definitions of Electrical Terms. A.I.E.E., 1941.

2. WARE, L. A., and H. R. REED. Communication Circuits. John Wiley & Sons.

3. EVERITT, W. L. Communication Engineering. McGraw-Hill Book Co.

4. SHEA, T. E. Transmission Networks and Wave Filters. D. Van Nostrand Co.

5. JOHNSON, K. S. Transmission Circuits for Telephonic Communication. D. Van Nostrand Co.

6. THIESSEN, ARTHUR E, Volume Control in Voice Circuit. General Radio Experimenter, June, 1931, Vol. 6, No. 1.

7. MASON, W. P. Electromechanical Transducers and Wave Filters. D. Van Nostrand Co.

8. CAMPBELL, G. A. Physical Theory of the Electric Wave-Filter. Bell System Tech. J., November, 1922, Vol. 1, No. 2.

9. BUCKLEY, O. E. The Evolution of the Crystal Wave Filter. Bell Telephone Quarterly, January, 1937, Vol. 16, No, 1.

10. MASON, W. P. Electrical Wave Filters Employing Quartz Crystals as Elements. Bell System Tech. J., July, 1934, Vol. 13, No, 3,

11. MASON, W. P. Quartz Crystal Filters. Bell Lab. Record, June, 1935, Vol. 13, No. 10.

12. LANE, C. E. Duplex Crystals. Bell Lab. Record, February, 1946, Vol. 24, No. 2.

13. BURNS, G. K. Manufacture of Quartz Crystal Filters. Bell System Tech. J., October, 1940, Vol. 19, No. 4.

14. WILLIS, E. S. A New Crystal Channel Filter for Broad Band Carrier Systems. Elec. Eng._t March, 1946, Vol. 65, No. 3.

15. MASON, W. P. New Low-Coefficient Synthetic Piezoelectric Crystals for Use in Filters and Oscillators. Proc. I.R.E., October, 1947, Vol. 35, No. 10.