Add CC BY 4.0 license and source credits

README.md

@@ -1,5 +1,6 @@
 ---
 language: []
+license: cc-by-4.0
 task_categories:
 - text-classification
 pretty_name: Perch Bug Pairs — Public
@@ -49,3 +50,19 @@ Each side contains `revision`, `path`, `method_name`, `source`, `source_sha256`,
 | `lua` | 19 |
 
 **File SHA-256:** `32bc68bc85d5535ad28e103adbfa0c09c73e09d0f53a53f7ca35ec219a96e6e2`
+
+## Sources
+
+Every pair is pinned to two revisions of a public repository. `source_datasets` names the collection it came from, where one was recorded.
+
+| Source | Pairs |
+| --- | ---: |
+| [SWE-rebench-V2](https://huggingface.co/datasets/nebius/SWE-rebench-V2) | 1,676 |
+| [SWE-bench](https://huggingface.co/datasets/princeton-nlp/SWE-bench) | 229 |
+| [BugsInPy](https://github.com/soarsmu/BugsInPy) | 4 |
+| Other open-source commits and pull requests | 107 |
+| No source recorded | 204 |
+
+## License
+
+Labels, Perch method context and this card: [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/). Method source code keeps its repository's license. We use SWE-rebench-V2 pairs under its CC BY 4.0 license.