Liu, M. H., and Y. C. Guo. 2026. “Incremental Vs. Stock: Evaluating the Impact of VAT Credit Refunds on Corporate Productivity With Evidence from Difference-in-Differences and Machine Learning Heterogeneity Analysis”. Advanced Electromagnetics 15 (3):4230-48. https://doi.org/10.7716/aem.v15i3.3486.