@article{CMUC_2009_50_1_a6,
     author = {Herzog, Gerd and Schmoeger, Christoph},
     title = {A universal property of $C_0$-semigroups},
     journal = {Commentationes Mathematicae Universitatis Carolinae},
     pages = {83--88},
     year = {2009},
     volume = {50},
     number = {1},
     mrnumber = {2562805},
     zbl = {1212.47018},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CMUC_2009_50_1_a6/}
}