Radio instruments and measurements: Circular of the Bureau of Standards, No. 74. Second edition, paper, 345 pages, illustrations, 7″ × 10″. First edition prepared by J. H. Dellinger, J. M. Miller and F. W. Grover, assisted by G. C. Southworth and other members of the radio laboratory. Revision for second edition made by J. H. Dellinger, L. E. Whittemore and R. S. Ould. Washington, D. C., Government Printing Office, 1924. Price, sixty cents. Sold only by the Superintendent of Documents, Government Printing Office, Washington, D. C.