Novel fully-heterogeneous GNN designs for track reconstruction at the HL-LHCSylvain Caillou, Christophe Collard, Charline Rougier, Jan Stark, Heberth Torres and Alexis VallierEPJ Web of Conf., 295 (2024) 09028DOI: https://doi.org/10.1051/epjconf/202429509028