@article{01208005,
title = {Galilei Laguerre geometry and rational circular offset surfaces.},
journal = {Beitr\"age zur Algebra und Geometrie},
volume = {39},
year = {1998},
pages = {291-305},
zbl = {0917.51003},
language = {en},
url = {http://dml.mathdoc.fr/item/01208005}
}
Wallner, Johannes; Chen, Horng-Yang; Pottmann, Helmut. Galilei Laguerre geometry and rational circular offset surfaces.. Beiträge zur Algebra und Geometrie, Tome 39 (1998) pp. 291-305. http://gdmltest.u-ga.fr/item/01208005/