INFORMATION TO CONTRIBUTORS 
Thr Proceedings is the official organ of the Nationai. Academy op 
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in giving the relation of the paper to previous publications of the author 
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inclusive pages. For example: Montgomery, T. H., J, Morph., Boston, 
22, 1911 (731-815); or, Wheeler, W. M., Kdnigsburg, Schr. physik. Ges,, 
55, 1914 (1-142). 
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