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Transactions of the American Mathematical Society

Published by the American Mathematical Society since 1900, Transactions of the American Mathematical Society is devoted to longer research articles in all areas of pure and applied mathematics.

ISSN 1088-6850 (online) ISSN 0002-9947 (print)

The 2020 MCQ for Transactions of the American Mathematical Society is 1.48.

What is MCQ? The Mathematical Citation Quotient (MCQ) measures journal impact by looking at citations over a five-year period. Subscribers to MathSciNet may click through for more detailed information.


The space of retractions of the $2$-sphere and the annulus
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by Neal R. Wagner PDF
Trans. Amer. Math. Soc. 158 (1971), 319-329 Request permission


Given a manifold $M$, there is an embedding $\Lambda$ of $M$ into the space of retractions of $M$, taking each point to the retraction of $M$ to that point. Considering $\Lambda$ as a map into the connected component containing its image, we prove that $\Lambda$ is a weak homotopy equivalence for two choices of $M$, namely, the $2$-sphere and the annulus.
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Additional Information
  • © Copyright 1971 American Mathematical Society
  • Journal: Trans. Amer. Math. Soc. 158 (1971), 319-329
  • MSC: Primary 54.28
  • DOI:
  • MathSciNet review: 0279763