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Summary
DescriptionAlexander horned sphere construction (Alexander 1924).jpg
English: Diagram of the first few iterative steps in the construction of Alexander's horned sphere, from Alexander's original 1924 paper.
Date
Source
Alexander, J. W. (1924), "An Example of a Simply Connected Surface Bounding a Region which is not Simply Connected", Proceedings of the National Academy of Sciences of the United States of America, National Academy of Sciences, 10 (1): 8–10
Author
Alexander, J. W.
Licensing
Public domainPublic domainfalsefalse
This work is in the public domain in the United States because it was published (or registered with the U.S. Copyright Office) before January 1, 1929.
Public domain works must be out of copyright in both the United States and in the source country of the work in order to be hosted on the Commons. If the work is not a U.S. work, the file must have an additional copyright tag indicating the copyright status in the source country. Note: This tag should not be used for sound recordings.PD-1923Public domain in the United States//commons.wikimedia.org/wiki/File:Alexander_horned_sphere_construction_(Alexander_1924).jpg
Captions
Construction of Alexander's horned sphere
Items portrayed in this file
depicts
copyright status
public domain
media type
image/jpeg
checksum
81acc213a58aa1d537f1ad9349e9662768c103ae
determination method: SHA-1
data size
79,102 byte
height
592 pixel
width
896 pixel
inception
1924
File history
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00:26, 9 February 2021
896 × 592 (77 KB)
Adumbrativus
Uploaded a work by Alexander, J. W. from Alexander, J. W. (1924), "An Example of a Simply Connected Surface Bounding a Region which is not Simply Connected", Proceedings of the National Academy of Sciences of the United States of America, National Academy of Sciences, 10 (1): 8–10 with UploadWizard
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