Liu, M. H. and Guo, Y. C. (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), pp. 4230–4248. doi: 10.7716/aem.v15i3.3486.