@article {Agrachev2017,
	title = {Homotopically invisible singular curves},
	journal = {Calculus of Variations and Partial Differential Equations},
	volume = {56},
	number = {4},
	year = {2017},
	month = {Jul},
	pages = {105},
	issn = {1432-0835},
	doi = {10.1007/s00526-017-1203-z},
	url = {https://doi.org/10.1007/s00526-017-1203-z},
	author = {Andrei A. Agrachev and Francesco Boarotto and Antonio Lerario}
}
@article {boarotto2017homotopy,
	title = {Homotopy properties of horizontal path spaces and a theorem of Serre in subriemannian geometry},
	journal = {Communications in Analysis and Geometry},
	volume = {25},
	number = {2},
	year = {2017},
	pages = {269{\textendash}301},
	publisher = {International Press of Boston},
	doi = {10.4310/CAG.2017.v25.n2.a1},
	author = {Francesco Boarotto and Antonio Lerario}
}
