R. A. Emerson and C. B. Hutchison
THE RELATIVE FREQUENCY OF CROSSING OVER IN MICROSPORE AND IN MEGASPORE DEVELOPMENT IN MAIZE
Genetics 1921 6: 417–432
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D. F. Jones
THE INDETERMINATE GROWTH FACTOR IN TOBACCO AND ITS EFFECT UPON DEVELOPMENT
Genetics 1921 6: 433–444
[PDF]  

F. B. Sumner and R. R. Huestis
BILATERAL ASYMMETRY AND ITS RELATION TO CERTAIN PROBLEMS OF GENETICS
Genetics 1921 6: 445–485
[PDF]