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- [43] Characteristics of the ionosphere at Washington, D. C., July 1937 PROCEEDINGS OF THE INSTITUTE OF RADIO ENGINEERS, 1937, 25 (09): : 1188 - 1191
- [44] NEW SALARY SCHEDULE IN WASHINGTON, D. C., SCHOOLS SCHOOL AND SOCIETY, 1924, 20 (514): : 562 - 563
- [45] Characteristics of the ionosphere at Washington, D. C., January, 1938 PROCEEDINGS OF THE INSTITUTE OF RADIO ENGINEERS, 1938, 26 (03): : 379 - 382
- [47] Characteristics of the ionosphere at Washington, D. C., July, 1938 PROCEEDINGS OF THE INSTITUTE OF RADIO ENGINEERS, 1938, 26 (09): : 1171 - 1174