License
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- All rights reserved57
- CC0 1.0 Universal54
- Public Domain Mark 1.038
- Attribution-NonCommercial-NoDerivatives 4.0 (CC BY-NC-ND 4.0)30
- Attribution-NonCommercial-NoDerivs 3.0 United States28
- Attribution-NonCommercial 4.0 (CC BY-NC 4.0)11
- Attribution-NonCommercial-ShareAlike 3.0 United States8
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- Attribution-NoDerivatives 4.0 (CC BY-ND 4.0)3
- Attribution-NonCommercial-ShareAlike 4.0 (CC BY-NC-SA 4.0)3
- Attribution-ShareAlike 3.0 United States1