Mishima, K.K.MishimaHayashi, M.M.HayashiYi, J.J.YiLin, S. H.S. H.LinSelzle, H. L.H. L.SelzleSchlag, E. W.E. W.Schlag2020-04-012020-04-012002https://scholars.lib.ntu.edu.tw/handle/123456789/482723Generalization of Keldysh's theoryjournal article10.1103/PhysRevA.66.033401