INFORMATION TO CONTRIBUTORS 
The Proceedings is the official organ of the National Academy op 
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iiling to 
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e pages. For example: Montgomery, T. H., /. Morph., Boston, 
x911 (731-815); or, Wheeler, W. M., Konigsbnrg, Schr. physik. Ges., 
55, 1914 (1-142). 
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Copyright, 1921, by the National Academy of Sciences 
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