Junhua Shi Qingyun Sun Haonan Yuan Xingcheng Fu SA²GFM: Enhancing Robust Graph Foundation Models with Structure-Aware Semantic Augmentation. 15716-15724 2026 AAAI https://doi.org/10.1609/aaai.v40i18.38602 conf/aaai/2026 db/conf/aaai/aaai2026.html#ShiSYF26