Nakashima, S. and Maehara, T. 2019. Subspace Selection via DR-Submodular Maximization on Lattices. Proceedings of the AAAI Conference on Artificial Intelligence. 33, 01 (Jul. 2019), 4618-4625. DOI:https://doi.org/10.1609/aaai.v33i01.33014618.