@article {jackson2016effects,
	title = {Effects of heavy alkali elements in Cu (In, Ga) Se<sub>2</sub> solar cells with efficiencies up to 22.6\%},
	journal = {physica status solidi (RRL){\textendash}Rapid Research Letters},
	volume = {10},
	year = {2016},
	pages = {583{\textendash}586},
	author = {Jackson, Philip and Wuerz, Roland and Hariskos, Dimitrios and Lotter, Erwin and Witte, Wolfram and Powalla, Michael}
}
@article {powalla2013high,
	title = {High-efficiency Cu(In,Ga)Se<sub>2</sub> cells and modules},
	journal = {Solar energy materials and solar cells},
	volume = {119},
	year = {2013},
	pages = {51{\textendash}58},
	author = {Powalla, Michael and Jackson, Philip and Witte, Wolfram and Hariskos, Dimitrios and Paetel, Stefan and Tschamber, Carsten and Wischmann, Wiltraud}
}
