Wang, FarnFarnWangMok, Aloysius K.Aloysius K.MokFARN WANG2020-06-042020-06-041994https://scholars.lib.ntu.edu.tw/handle/123456789/497114RTL and Refutation by Positive Cycles.conference paper10.1007/3-540-58555-9_121https://doi.org/10.1007/3-540-58555-9_121