@article{10_4064_cm98_1_5,
     author = {Isaac Kornfeld and Wojciech Kosek},
     title = {Positive $L^1$ operators associated with
 nonsingular mappings and an example of {E.} {Hille}},
     journal = {Colloquium Mathematicum},
     pages = {63--77},
     publisher = {mathdoc},
     volume = {98},
     number = {1},
     year = {2003},
     doi = {10.4064/cm98-1-5},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/cm98-1-5/}
}