@article {2007,
	title = {Gaussian estimates for hypoelliptic operators via optimal control},
	journal = {Atti Accad. Naz. Lincei Cl. Sci. Fis. Mat. Natur. Rend. Lincei (9) Mat. Appl. 18 (2007) 333-342},
	number = {SISSA;45/2007/M},
	year = {2007},
	abstract = {We obtain Gaussian lower bounds for the fundamental solution of a class of hypoelliptic equations, by using repeatedly an invariant Harnack inequality. Our main result is given in terms of the value function of a suitable optimal control problem.},
	doi = {10.4171/RLM/499},
	url = {http://hdl.handle.net/1963/1994},
	author = {Ugo Boscain and Sergio Polidoro}
}
