@article{GDZPPN002481065,
title = {Quasiregular Points and Time Changes.},
journal = {Monatshefte f\"ur Mathematik},
volume = {85},
year = {1978},
pages = {245-252},
zbl = {0398.28022},
url = {http://dml.mathdoc.fr/item/GDZPPN002481065}
}
Veech, William A. Quasiregular Points and Time Changes.. Monatshefte für Mathematik, Tome 85 (1978) pp. 245-252. http://gdmltest.u-ga.fr/item/GDZPPN002481065/