diff --git a/letter.bib b/letter.bib
new file mode 100644
index 0000000..bf3a5ba
--- /dev/null
+++ b/letter.bib
@@ -0,0 +1,104 @@
+@ARTICLE{ADMM,
+  author={Barman, Siddharth and Liu, Xishuo and Draper, Stark C. and Recht, Benjamin},
+  journal={IEEE Transactions on Information Theory}, 
+  title={Decomposition Methods for Large Scale LP Decoding}, 
+  year={2013},
+  volume={59},
+  number={12},
+  pages={7870-7886},
+%  doi={10.1109/TIT.2013.2281372}
+}
+
+@ARTICLE{feldman_paper,
+  author={Feldman, J. and Wainwright, M.J. and Karger, D.R.},
+  journal={IEEE Transactions on Information Theory}, 
+  title={Using linear programming to Decode Binary linear codes}, 
+  year={2005},
+  volume={51},
+  number={3},
+  pages={954-972},
+%  doi={10.1109/TIT.2004.842696}
+}
+
+@ARTICLE{ml_in_the_list,
+	author={Geiselhart, Marvin and Elkelesh, Ahmed and Ebada, Moustafa and Cammerer, Sebastian and Brink, Stephan ten},
+	journal={IEEE Transactions on Communications}, 
+	title={Automorphism Ensemble Decoding of Reed–Muller Codes}, 
+	year={2021},
+	volume={69},
+	number={10},
+	pages={6424-6438},
+%	doi={10.1109/TCOMM.2021.3098798}
+}
+
+@ARTICLE{mackay99,
+  author={MacKay, D.J.C.},
+  journal={IEEE Transactions on Information Theory}, 
+  title={Good error-correcting codes based on very sparse matrices}, 
+  year={1999},
+  volume={45},
+  number={2},
+  pages={399-431},
+%  doi={10.1109/18.748992}
+}
+
+@online{mackay,
+    author = {MacKay, David J.C.},
+    title  = {Encyclopedia of Sparse Graph Codes},
+    date   = {2023-04},
+    url    = {http://www.inference.org.uk/mackay/codes/data.html}
+}
+
+@article{proximal_algorithms,
+  title={Proximal algorithms},
+  author={Parikh, Neal and Boyd, Stephen and others},
+  journal={Foundations and trends{\textregistered} in Optimization},
+  volume={1},
+  number={3},
+  pages={127--239},
+  year={2014},
+  publisher={Now Publishers, Inc.}
+}
+
+@book{channel_codes_book,
+    place={Cambridge},
+    title={Channel Codes: Classical and Modern},
+%    DOI={10.1017/CBO9780511803253},
+    publisher={Cambridge University Press},
+    author={Ryan, William and Lin, Shu},
+    year={2009},
+%    url={https://d1.amobbs.com/bbs_upload782111/files_35/ourdev_604508GHLFR2.pdf}
+}
+
+@INPROCEEDINGS{adaptive_lp_decoding,
+  author={Taghavi, Mohammad H. and Siegel, Paul H.},
+  booktitle={2006 IEEE International Symposium on Information Theory}, 
+  title={Adaptive Linear Programming Decoding}, 
+  year={2006},
+  volume={},
+  number={},
+  pages={1374-1378},
+%  doi={10.1109/ISIT.2006.262071}
+}
+
+@INPROCEEDINGS{interior_point_decoding,
+  author={Vontobel, Pascal O.},
+  booktitle={2008 Information Theory and Applications Workshop}, 
+  title={Interior-point algorithms for linear-programming decoding}, 
+  year={2008},
+  volume={},
+  number={},
+  pages={433-437},
+%  doi={10.1109/ITA.2008.4601085}
+}
+
+@article{proximal_paper,
+    title={Proximal Decoding for {LDPC} Codes},
+    author={Tadashi Wadayama and Satoshi Takabe},
+    journal={IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences},
+%    volume={advpub},
+%    pages={2022TAP0002},
+    year={2022},
+%    doi={10.1587/transfun.2022TAP0002}
+}
+
diff --git a/letter.tex b/letter.tex
index 2c94b92..e8fca82 100644
--- a/letter.tex
+++ b/letter.tex
@@ -9,6 +9,12 @@
 \usepackage{dsfont}
 \usepackage{mleftright}
 \usepackage{bbm}
+\usepackage[
+	backend=biber,
+	style=ieee,
+	sorting=nty,
+]{biblatex}
+
 
 \usepackage{tikz}
 \usetikzlibrary{spy, arrows.meta,arrows}
@@ -39,6 +45,8 @@
 	\input{lib/latex-common/common.tex}
 \fi
 
+\addbibresource{letter.bib}
+\AtBeginBibliography{\footnotesize}
 
 \pgfplotsset{colorscheme/cel}
 
@@ -778,41 +786,7 @@ Ministry of Education and Research (BMBF) within the project Open6GHub
 %
 
 
-\begin{thebibliography}{1}
-\bibliographystyle{IEEEtran}
-
-\bibitem{ADMM}
-S. Barman, X. Liu, S. C. Draper and B. Recht, ``Decomposition Methods for Large Scale LP Decoding,'' in IEEE Transactions on Information Theory, vol. 59, no. 12, pp. 7870-7886, Dec. 2013, doi: 10.1109/TIT.2013.2281372.
-
-\bibitem{feldman_paper}
-J. Feldman, M. J. Wainwright and D. R. Karger, ``Using linear programming to Decode Binary linear codes,'' in IEEE Transactions on Information Theory, vol. 51, no. 3, pp. 954-972, March 2005, doi: 10.1109/TIT.2004.842696.
-
-\bibitem{ml_in_the_list}
-M. Geiselhart, A. Elkelesh, M. Ebada, S. Cammerer and S. t. Brink, ``Automorphism Ensemble Decoding of Reed–Muller Codes,'' in IEEE Transactions on Communications, vol. 69, no. 10, pp. 6424-6438, Oct. 2021, doi: 10.1109/TCOMM.2021.3098798.
-
-\bibitem{mackay99}
-D. J. C. MacKay, ``Good error-correcting codes based on very sparse matrices,'' in IEEE Transactions on Information Theory, vol. 45, no. 2, pp. 399-431, March 1999, doi: 10.1109/18.748992.
-
-\bibitem{mackay}
-D.J.C. MacKay, ``Encyclopedia of sparse graph codes [online],''
-Available: http://www.inference.phy.cam.ac.uk/mackay/codes/data.html
-
-\bibitem{proximal_algorithms}
-N. Parikh and S. Boyd,``Proximal algorithms,'' Found. Trends Optim., vol. 1, no. 3, pp. 127–239, Jan. 2014.
-
-\bibitem{channel_codes_book}
-W. Ryan and S. Lin, Channel Codes: Classical and Modern, Cambridge, Cambridge University Press, 2009, pp. 651-670.
-
-\bibitem{adaptive_lp_decoding}
-M. H. Taghavi and P. H. Siegel, ``Adaptive Linear Programming Decoding,'' 2006 IEEE International Symposium on Information Theory, Seattle, WA, USA, 2006, pp. 1374-1378, doi: 10.1109/ISIT.2006.262071.
-
-\bibitem{interior_point_decoding}
-P. O. Vontobel, ``Interior-point algorithms for linear-programming decoding,'' 2008 Information Theory and Applications Workshop, San Diego, CA, USA, 2008, pp. 433-437, doi: 10.1109/ITA.2008.4601085.
-
-\bibitem{proximal_paper}
-T. Wadayama and S. Takabe, ``Proximal decoding for ldpc codes'' IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, vol. advpub, 2022TAP0002, 2022.
-
-\end{thebibliography}
-
+\printbibliography
 
 \end{document}
+