@article {ambrosio2012light,
	title = {Light-induced spiral mass transport in azo-polymer films under vortex-beam illumination},
	journal = {Nature communications},
	volume = {3},
	year = {2012},
	pages = {989},
	publisher = {Nature Publishing Group},
	author = {Ambrosio, Antonio and Marrucci, Lorenzo and Borbone, Fabio and Roviello, Antonio and Maddalena, Pasqualino}
}
