Zhang, Qi, Longbing Cao, Chongyang Shi, and Liang Hu. 2021. “Tripartite Collaborative Filtering With Observability and Selection for Debiasing Rating Estimation on Missing-Not-at-Random Data”. Proceedings of the AAAI Conference on Artificial Intelligence 35 (5):4671-78. https://doi.org/10.1609/aaai.v35i5.16597.