@article {1113491,
	title = {Meta-Lens Doublet in the Visible Region},
	journal = {Nano Letters},
	year = {2017},
	url = {http://pubs.acs.org/doi/abs/10.1021/acs.nanolett.7b01888},
	author = {Benedikt Groever and Wei Ting Chen and Federico Capasso}
}
