Royalty-Free Mathematical Photos, dominant color: gray
- 2576x1316 Public Domain
- 3648x2736 Public Domain
- 4608x3072 Public Domain
- 4640x3080 Public Domain
- 5472x3648 Public Domain
- 5676x3784 Public Domain
- 4556x3037 Public Domain
- 4608x3456 Public Domain
- 2000x1649 Public Domain
- 3162x2000 Public Domain
- 5676x3784 Public Domain
- 6000x4000 Public Domain
- 4900x2864 Public Domain
- 8000x4203 Public Domain
- 5616x3744 Public Domain
- 3504x2336 Public Domain