Feng, C. and Qian, C. 2021. Multi-Objective Submodular Maximization by Regret Ratio Minimization with Theoretical Guarantee. Proceedings of the AAAI Conference on Artificial Intelligence. 35, 14 (May 2021), 12302-12310. DOI:https://doi.org/10.1609/aaai.v35i14.17460.