Update README.md

README.md

@@ -20,7 +20,7 @@ dataset_summary: >
 # Metamath Proof Graphs (10k)
 
 This repository provides a PyTorch Geometric dataset designed for the TAG-DS TopoBench challenge.  
-It contains **20,000 graphs total:** 10,000 theorem-only DAGs and 10,000 full proof DAGs drawn from the first 10k theorems in the Metamath database.
+It contains **20,000 graphs total:** 10,000 theorem-only DAGs and 10,000 full proof DAGs drawn from the first 10k theorems in the Metamath [1] database.
 
 ## Contents
 
@@ -66,7 +66,7 @@ This pairing enables:
 - Graph type: **directed acyclic graphs (DAGs)**  
 - Label space: **3,557 justification labels**, where all labels with <5 training occurrences are collapsed into `UNK`  
 - **Conclusion masking:** the conclusion node’s embedding is zeroed out; the model must infer its label from the structure and other nodes  
-- **Monotonicity constraint:** in Metamath, proofs only use theorems with index ≤ the current theorem, so later theorems never appear in earlier graphs  
+- **Monotonicity constraint:** in Metamath, proofs only use theorems with index <= the current theorem, so later theorems never appear in earlier graphs  
 - Theorem-only graphs are included in training as prior knowledge for downstream proof prediction.
 
 ---
@@ -83,3 +83,17 @@ slices    = obj["slices"]
 train_idx = obj["train_idx"]
 val_idx   = obj["val_idx"]
 test_idx  = obj["test_idx"]
+```
+
+---
+
+## Acknowledgements
+
+Thanks to the Erdős Institute for providing the project-based, collaborative
+environment where key components of the preprocessing pipeline were first
+developed.
+
+---
+
+## References
+[1] Metamath Official Site — <https://us.metamath.org/index.html>