| Dunn's cluster validity index as a contrast measure of VAT images Recent countries visiting this post |  |
 | 12 | United States |
 | 3 | Russian Federation |
 | 1 | Romania |
 | 1 | Turkey |
 | 1 | Belgium |
 | 1 | Taiwan |
| Dunn's cluster validity index as a contrast measure of VAT images Recent countries visiting this post | |
| 12 | United States |
| 3 | Russian Federation |
| 1 | Romania |
| 1 | Turkey |
| 1 | Belgium |
| 1 | Taiwan |