@article{10_4153_CJM_1997_011_0,
     author = {Coll, B. and Gasull, A. and Prohens, R.},
     title = {Differential {Equations} {Defined} by the {Sum} of two {Quasi-Homogeneous} {Vector} {Fields}},
     journal = {Canadian journal of mathematics},
     pages = {212--231},
     year = {1997},
     volume = {49},
     number = {2},
     doi = {10.4153/CJM-1997-011-0},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-1997-011-0/}
}