Cheng, H.H.ChengER-CHENG TSAIZhu, X.X.Zhu2019-12-202019-12-201982https://scholars.lib.ntu.edu.tw/handle/123456789/436824journal article10.1103/PhysRevD.26.9082-s2.0-0041349897https://www.scopus.com/inward/record.uri?eid=2-s2.0-0041349897&doi=10.1103%2fPhysRevD.26.908&partnerID=40&md5=df6b302d46f39dc6e4a52a3b68c50087