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S. B. Townes, E. P. Starke, M. S. Robertson, Isabella Burdick, Albert Farnell, H. C. D. McClusky, Paul D. Thomas, D. L. MacKay, F. A. Foraker, G. W. Wishard, N. A. Court, W. V. Parker, James F. Callicott, H. T. R. Aude, V. Thebault, Problem Department, National Mathematics Magazine, Vol. 16, No. 5 (Feb., 1942), pp. 259-266
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