@article{10_4064_sm179_2_4,
     author = {Piotr Budzy/nski and Jan Stochel},
     title = {Joint subnormality of $n$-tuples and
 $C_0$-semigroups of composition operators on $L^2$-spaces},
     journal = {Studia Mathematica},
     pages = {167--184},
     year = {2007},
     volume = {179},
     number = {2},
     doi = {10.4064/sm179-2-4},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/sm179-2-4/}
}