@article {Sabatini2013,
	title = {Nonlocal van der Waals density functional made simple and efficient},
	journal = {Physical Review B},
	volume = {87},
	number = {4},
	year = {2013},
	month = {jan},
	pages = {041108},
	doi = {10.1103/PhysRevB.87.041108},
	author = {Sabatini, Riccardo and Gorni, Tommaso and de Gironcoli, Stefano}
}
