Nikolaos Rodis, Christos Sardianos, Panagiotis I. Radoglou-Grammatikis, Panagiotis G. Sarigiannidis, Iraklis Varlamis, Georgios Th. Papadopoulos: Multimodal Explainable Artificial Intelligence: A Comprehensive Review of Methodological Advances and Future Research Directions. IEEE Access 12: 159794-159820 (2024)