@article{05904696,
title = {Second order differential invariants of linear frames.},
journal = {Balkan Journal of Geometry and its Applications (BJGA)},
volume = {15},
year = {2010},
pages = {14-25},
zbl = {1220.53018},
language = {en},
url = {http://dml.mathdoc.fr/item/05904696}
}
Brajerčík, Ján. Second order differential invariants of linear frames.. Balkan Journal of Geometry and its Applications (BJGA), Tome 15 (2010) pp. 14-25. http://gdmltest.u-ga.fr/item/05904696/