Luo, Yunpeng, Jiayi Ji, Xiaoshuai Sun, Liujuan Cao, Yongjian Wu, Feiyue Huang, Chia-Wen Lin, and Rongrong Ji. “Dual-Level Collaborative Transformer for Image Captioning”. Proceedings of the AAAI Conference on Artificial Intelligence 35, no. 3 (May 18, 2021): 2286-2293. Accessed October 16, 2021. https://ojs.aaai.org/index.php/AAAI/article/view/16328.