Benchmarking Non-Hardware Balance of System (Soft) Costs for U.S. Photovoltaic Systems Using a Data-Driven Analysis from PV Installer Survey Results. 2012. LBNL-5963E..
"Quantifying non-hardware balance of system costs for photovoltaic installations in the United States using a combined annual expenditure-labor hour productivity approach." 2012 38th IEEE Photovoltaic Specialists Conference. Austin, TX, USA: IEEE, 2012. 001762 - 001767..