License
- Attribution 3.0 United States193
- Attribution 4.0 (CC BY 4.0)150
- All rights reserved66
- CC0 1.0 Universal47
- Public Domain Mark 1.032
- Attribution-NonCommercial-NoDerivs 3.0 United States30
- Attribution-NonCommercial-NoDerivatives 4.0 (CC BY-NC-ND 4.0)20
- Attribution-NonCommercial 4.0 (CC BY-NC 4.0)14
- Attribution-NonCommercial-ShareAlike 3.0 United States7
- Attribution-NonCommercial-ShareAlike 4.0 (CC BY-NC-SA 4.0)3
- Attribution-NoDerivatives 4.0 (CC BY-ND 4.0)1
- Attribution-NonCommercial 3.0 United States1
- Attribution-ShareAlike 3.0 United States1