INFORMATION TO CONTRIBUTORS 
The Proceedings is the official organ of the National Academy' of 
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brief accounts of important current researches of members of the Academy 
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to secure prompt publication of original announcements . of discoveries 
and wide circulation of the results of American research among investi- 
gators in other countries and in all branches of science. 
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in giving the relation of the paper to previous publications of the author 
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International Catalogue of Scientific Literature, viz., name of author, 
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inclusive pages. For example: Montgomery, T. H., J. Morph., Boston, 
22, 1911 (731-815); or, Wheeler, W. M., Konigsburg, Schr. physik. Ges., ' 
55, 1914 (1-142). 
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Wilson, Managing Editor, Mass. Institute of Technology, Cambridge, 
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