Oliveira, M., B. J. Vergilio, R. R. Sobrinho, J. Silva, and A. de L. Fontão. “Metamorphic Fairness Testing of Retrieval-Augmented Generation: Diagnosing Retriever Bias and Evaluating Graph-Based Mitigation”. Journal of Software Engineering Research and Development, vol. 14, no. 1, Aug. 2026, pp. 179-08, doi:10.5753/jserd.2026.7713.