| Outer-Layer Based Tracking using Entropy as a Similarity Measure Recent countries visiting this post |  |
 | 7 | United States |
 | 1 | France |
 | 1 | |
 | 1 | China |
| Outer-Layer Based Tracking using Entropy as a Similarity Measure Recent countries visiting this post | |
| 7 | United States |
| 1 | France |
| 1 | |
| 1 | China |