update PyPartMC paper info in README (arXiv -> SoftwareX; 2023 -> 2024) (#342)

Author: slayoo

README.md

@@ -7,7 +7,7 @@ PyPartMC is a Python interface to [PartMC](https://lagrange.mechse.illinois.edu/
 PyPartMC is implemented in C++ and it also constitutes a C++ API to the PartMC Fortran internals.
 The Python API can facilitate using PartMC from other environments - see, e.g., Julia and Matlab examples below.
 
-For an outline of the project, rationale, architecture, and features, refer to: [D'Aquino et al., 2023 (arXiv)](https://doi.org/10.48550/arXiv.2308.02052) (please cite if PyPartMC is used in your research).
+For an outline of the project, rationale, architecture, and features, refer to: [D'Aquino et al., 2024 (SoftwareX)](https://doi.org/10.1016/j.softx.2023.101613) (please cite if PyPartMC is used in your research).
 For a list of talks and other relevant resources, please see [project Wiki](https://github.com/open-atmos/PyPartMC/wiki/).
 
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