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Summary
editDescription | Part of a page from Gunning (1966), a set of typewritten lecture notes which were published directly as provided by the author. This portion shows the mixture of hand-written and type-written symbols, along with "blackboard bold" style letters for R and C achieved by double-striking each letter with significant offset between strikes. Using these symbols for real and complex numbers was new at the time but is now pervasive in technical literature.
Gunning, Robert C. (1966) Lectures on Riemann Surfaces. Mathematical Notes. Princeton University Press. p. 1. https://archive.org/details/lecturesonrieman0000unse/page/1/mode/1up |
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Author or copyright owner |
Robert C. Gunning |
Source (WP:NFCC#4) | https://archive.org/details/lecturesonrieman0000unse/page/1/mode/1up |
Date of publication | 1966 |
Use in article (WP:NFCC#7) | Blackboard bold |
Purpose of use in article (WP:NFCC#8) | This is an illustrative image showing a typewritten document from the 1960s near the beginning of the use of 'blackboard bold' type in mathematics. |
Not replaceable with free media because (WP:NFCC#1) |
The software or website from which the screenshot is taken is copyrighted and not released under a free license, so creation of a free image is not possible. |
Not replaceable with textual coverage because (WP:NFCC#1) |
A plain textual description does not adequately convey how these symbols were used in context in typewritten documents from 60 years ago. Any other available document published in the 1960s is also going to be copyrighted. |
Minimal use (WP:NFCC#3) | This is just a small decontextualized snippet of some mathematical lecture notes. It is not commercially interesting in and of itself. The resolution can't be much lower or the symbols will start to become illegible. |
Respect for commercial opportunities (WP:NFCC#2) |
The use of a low resolution screenshot from software or a website will not impact the commercial viability of the software or site. |
Fair useFair use of copyrighted material in the context of Blackboard bold//en.wikipedia.org/wiki/File:Blackboard_bold_in_typewritten_notes_from_Gunning_(1966).jpgtrue |
Licensing
editThis 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:
qualifies as fair use under United States copyright law. Any other uses of this image, on Wikipedia or elsewhere, may be copyright infringement. See Wikipedia:Non-free content and Wikipedia:Copyrights. | |||
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File history
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Date/Time | Thumbnail | Dimensions | User | Comment | |
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current | 02:07, 26 July 2023 | 880 × 624 (63 KB) | Jacobolus (talk | contribs) | make this a bit lower resolution. as it gets smaller it gets worse and worse at illustrating the topic, but this size is probably still okay | |
02:02, 26 July 2023 | No thumbnail | 1,257 × 891 (106 KB) | Jacobolus (talk | contribs) | This file was reduced to a size where it no longer illustrates the topic | |
00:02, 26 July 2023 | No thumbnail | 375 × 266 (75 KB) | DatBot (talk | contribs) | Reduce size of non-free image (BOT - disable) | |
16:50, 25 July 2023 | No thumbnail | 1,257 × 891 (106 KB) | Jacobolus (talk | contribs) | use a slightly lower resolution. any lower and it's going to stop clearly demonstrating the letters in question though | |
16:24, 25 July 2023 | No thumbnail | 1,796 × 1,273 (172 KB) | Jacobolus (talk | contribs) | Uploading an excerpt from a non-free work using File Upload Wizard |
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