Update README.md

README.md

@@ -42,5 +42,7 @@ Mathematical modelling has an important role in science, business, civic service
 <a href="https://www.sciencedirect.com/science/article/abs/pii/S095070512300730X" target="_blank" rel="noopener noreferrer"> Bahadorreza Ofoghi, John Yearwood: <b style="color:blue;">Knowledge representation of mathematical optimization problems and constructs for modeling [2023]</b> </a>
 
 <a href="https://arxiv.org/abs/2311.15271" target="_blank" rel="noopener noreferrer"> Qingyang Li, Lele Zhang, Vicky Mak-Hau: <b style="color:blue;">Synthesizing mixed-integer linear programming models from natural language descriptions [2023]</b> </a>
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+<a href="https://arxiv.org/abs/2011.06300" target="_blank" rel="noopener noreferrer"> Bahadorreza Ofoghi, Vicky Mak-Hau, John Yearwood: <b style="color:blue;">A Knowledge Representation Approach to Automated Mathematical Modelling [2021]</b> </a>
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