PNAS — Table of Contents — September 15, 1940, 26 (9)

September 15, 1940; 26 (9)

Astronomy

Astronomy:
- Theodore Eugene Sterne
A Note on the Variation of Delta Scuti
Proc Natl Acad Sci U S A 1940 26:537-541
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Astronomy:
- Harlow Shapley
Galactic and Extragalactic Studies
Proc Natl Acad Sci U S A 1940 26:541-548
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Astronomy:
- P. Swings
- and O. Struve
The Spectrum of BD +30°3639
Proc Natl Acad Sci U S A 1940 26:548-553
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Astronomy:
- Harlow Shapley
- and Rebecca B. Jones
Galactic and Extragalactic Studies
Proc Natl Acad Sci U S A 1940 26:554-561
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Mathematics:
- Samuel Eilenberg
On Homotopy Groups
Proc Natl Acad Sci U S A 1940 26:563-565
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Physics:
- Arthur E. Haas
On a General Rule Concerning the Half-Value Periods of Electron-Emitting Nuclei
Proc Natl Acad Sci U S A 1940 26:565-567
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Genetics:
- Norman Giles
THE EFFECT OF FAST NEUTRONS ON THE CHROMOSOMES OF TRADESCANTIA
Proc Natl Acad Sci U S A 1940 26:567-575
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Genetics:
- Harrison D. Stalker
CHROMOSOME HOMOLOGIES IN TWO SUB-SPECIES OF DROSOPHILA VIRILIS
Proc Natl Acad Sci U S A 1940 26:575-578
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Genetics:
- W. E. Castle
- and Helen Dean King
LINKAGE STUDIES OF THE RAT (RATTUS NORVEGICUS)
Proc Natl Acad Sci U S A 1940 26:578-580
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