@article {599,
	title = {Frobenius theorem and invariants for Hamiltonian systems},
	journal = {J. Phys. A: Math. Gen},
	volume = {34},
	year = {2001},
	pages = {1005},
	attachments = {https://professor.ufrgs.br/sites/default/files/fernando-haas/files/frobenius_theorem.pdf},
	author = {F. Haas}
}
