add blocked cholesky paper details and arxiv bib in main README

README.md

@@ -1 +1,21 @@
-# Manuscripts
+# Manuscripts
+
+This repository stores code and replication materials for papers related to the mixed-models packages in Julia.
+
+## Paper: Mixed-model Log-likelihood Evaluation Via a Blocked Cholesky Factorization
+
+This paper should be used when citing [`MixedModels.jl`](https://github.com/JuliaStats/MixedModels.jl)
+This pre-print for this paper is available on [arXiv](https://arxiv.org/abs/2505.11674).
+The code for this paper is in the `blockedcholesky` subdirectory.
+To cite the pre-print use the following bibtex:
+```bib
+@misc{bates2025mixedmodelloglikelihoodevaluationblocked,
+      title={Mixed-model Log-likelihood Evaluation Via a Blocked Cholesky Factorization},
+      author={Douglas Bates and Phillip M. Alday and Ajinkya H. Kokandakar},
+      year={2025},
+      eprint={2505.11674},
+      archivePrefix={arXiv},
+      primaryClass={stat.CO},
+      url={https://arxiv.org/abs/2505.11674},
+}
+```