ControlMLLM: Training-Free Visual Prompt Learning for Multimodal Large Language Models - Wu, Mingrui; Cai, Xinyue; Ji, Jiayi; Li, Jiale; Huang, Oucheng; Gen Luo; Fei, Hao; Jiang, Guannan; Sun, Xiaoshuai; Ji, Rongrong (Advances in Neural Information Processing Systems, 2024)