Update README.md

Author: TimWeaving

README.md

@@ -59,7 +59,7 @@ All this allows us to approach significantly larger systems than was previously
 ## How to cite
 When you use Symmer in a publication or other work, please cite the following:
 
-> Tim Weaving, Alexis Ralli, Peter J. Love, Sauro Succi, and Peter V. Coveney. *Contextual Subspace Variational Quantum Eigensolver Calculation of the Dissociation Curve of Molecular Nitrogen on a Superconducting Quantum Computer.* [arXiv preprint arXiv:2312.04392](https://arxiv.org/abs/2312.04392) (2023).
+> Tim Weaving, Alexis Ralli, Peter J. Love, Sauro Succi, and Peter V. Coveney. *Contextual subspace variational quantum eigensolver calculation of the dissociation curve of molecular nitrogen on a superconducting quantum computer.* [npj Quantum Information, 11(1), 25.](https://www.nature.com/articles/s41534-024-00952-4) (2025).
 
 > Alexis Ralli, Tim Weaving, Andrew Tranter, William M. Kirby, Peter J. Love, and Peter V. Coveney. *Unitary partitioning and the contextual subspace variational quantum eigensolver.* [Phys. Rev. Research 5, 013095](https://doi.org/10.1103/PhysRevResearch.5.013095) (2023).