OverLayBench: A Benchmark for Layout-to-Image Generation with Dense Overlaps - Li, Bingnan; Wang, Chen-Yu; Xu, Haiyang; Zhang, Xiang; Armand, Ethan; Srivastava, Divyansh; Xiaojun, Shan; Chen, Zeyuan; Xie, Jianwen; Tu, Zhuowen (Advances in Neural Information Processing Systems, 2025)