File:Bing's Dogbone.tiff

Summary

Media data and Non-free use rationale
Description	This figure illustrates one state of R.H. Bing's so-called "dogbone" construction, which was used to prove the n-dimensional Poincaré Conjecture
Author or copyright owner	R.H. Bing
Source (WP:NFCC#4)	Bulletin of the American Mathematical Society
Date of publication	1963
Use in article (WP:NFCC#7)	Dogbone space
Purpose of use in article (WP:NFCC#8)	The first stage of the construction of the doggone space
Not replaceable with free media because (WP:NFCC#1)	n.a.
Not replaceable with textual coverage because (WP:NFCC#1)	The figure illustrates necessarily spatial information that is not possible to know from the article alone
Minimal use (WP:NFCC#3)	I have only used the photo critical to understanding the construction of the space. I have used nothing else, in particular– no text, from the article appearing in the Bulletin or any other published source.
Respect for commercial opportunities (WP:NFCC#2)	n.a.
Fair useFair use of copyrighted material in the context of Dogbone space//en.wikipedia.org/wiki/File:Bing%27s_Dogbone.tifftrue

This work is copyrighted (or assumed to be copyrighted) and unlicensed. It does not fall into one of the blanket acceptable non-free content categories listed at Wikipedia:Non-free content § Images or Wikipedia:Non-free content § Audio clips, and it is not covered by a more specific non-free content license listed at Category:Wikipedia non-free file copyright templates. However, it is believed that the use of this work:

To illustrate the subject in question
Where no free equivalent is available or could be created that would adequately give the same information
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Fair use

	Date/Time	Thumbnail	Dimensions	User	Comment
current	01:09, 11 February 2018		481 × 208 (78 KB)	Ronhjones (talk \| contribs)	Reduced to NFC guideline
	05:14, 16 February 2015	No thumbnail	519 × 224 (66 KB)	Davidfsnyder (talk \| contribs)	Uploading an excerpt from a non-free work using File Upload Wizard