@article{01727489, title = {Engel structures with trivial characteristic foliations.}, journal = {Geometry \& Topology}, volume = {6}, year = {2002}, pages = {239-255}, doi = {10.2140/agt.2002.2.239}, zbl = {1008.53061}, language = {en}, url = {http://dml.mathdoc.fr/item/01727489} }
Adachi, Jiro. Engel structures with trivial characteristic foliations.. Geometry & Topology, Tome 6 (2002) pp. 239-255. doi : 10.2140/agt.2002.2.239. http://gdmltest.u-ga.fr/item/01727489/