| Topological phase transition in a network model with preferential attachment and node removal Recent countries visiting this post |  |
 | 8 | China |
 | 8 | United States |
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| Topological phase transition in a network model with preferential attachment and node removal Recent countries visiting this post | |
| 8 | China |
| 8 | United States |
| 5 | |
| 1 | Germany |
| 1 | Italy |