1. http://energy.gov/eere/sunshot/about-sunshot-initiative
. Accessed January 2016
2. http://pib.nic.in/newsite/PrintRelease.aspx?relid=122566
(2015)
3. P. Jackson et al., Properties of cu(in,Ga)Se2 solar cells with new record efficiencies up to 21.7%. Phys. Status Solidi RRL 9, 28–31 (2015)
4. A. Colthorpe, Thin-film competition hots up as TSMC Solar breaks day-old CIGS efficiency record. PVTech,
http://www.pv-tech.org/news/thin_film_competition_hots_up_as_tsmc_producer_breaks_day_old_cigs_efficien
(2015)
5. W. Wang et al., Device characteristics of CZTSSe thin-film solar cells with 12.6% efficiency. Adv. Energy Mater. 4, 1301456 (2014)