@article{MAN_1987__277_164274,
     author = {Ph. Cl\'ement and O. Diekmann and M. Gyllenberg and H.J.A.M. Heijmans and H.R. Thieme},
     title = {Perturbation {Theory} for {Dual} {Semigroups.} {I.} {The} {Sun-Reflexive} {Case.}},
     journal = {Mathematische Annalen},
     pages = {709--726},
     publisher = {mathdoc},
     volume = {277},
     year = {1987},
     zbl = {0634.47039},
     url = {http://geodesic.mathdoc.fr/item/MAN_1987__277_164274/}
}