Update README.md

README.md

@@ -48,6 +48,7 @@ julia> OMEinsum.timespace_complexity(optcode_sa, uniformsize(code, 2))
 
 If you find this package useful in your research, please cite the following papers
 
+To credit the `optimize_kahypar` and `optimize_sa` method,
 ```
 @misc{Pan2021,
       title={Simulating the Sycamore quantum supremacy circuits}, 
@@ -59,6 +60,22 @@ If you find this package useful in your research, please cite the following pape
 }
 ```
 
+To credit the `optimize_kahypar` method,
+```
+@Article{10.21468/SciPostPhys.7.5.060,
+	title={{Fast counting with tensor networks}},
+	author={Stefanos Kourtis and Claudio Chamon and Eduardo R. Mucciolo and Andrei E. Ruckenstein},
+	journal={SciPost Phys.},
+	volume={7},
+	issue={5},
+	pages={60},
+	year={2019},
+	publisher={SciPost},
+	doi={10.21468/SciPostPhys.7.5.060},
+	url={https://scipost.org/10.21468/SciPostPhys.7.5.060},
+}
+```
+
 ```
 @article{Gray2021,
    title={Hyper-optimized tensor network contraction},
@@ -75,5 +92,17 @@ If you find this package useful in your research, please cite the following pape
 }
 ```
 
+To credit the `optimize_tree` method,
+```
+@misc{kalachev2021recursive,
+      title={Recursive Multi-Tensor Contraction for XEB Verification of Quantum Circuits}, 
+      author={Gleb Kalachev and Pavel Panteleev and Man-Hong Yung},
+      year={2021},
+      eprint={2108.05665},
+      archivePrefix={arXiv},
+      primaryClass={quant-ph}
+}
+```
+
 ## Authors
 Jin-Guo Liu and Pan Zhang