1. Early markets: fuel cells for backup power;US Department of Energy Efficiency & Renewable Energy, Fuel Cell Technologies Office,2014
2. Fuel cells for critical communications backup power;Moreland,2008
3. Backup power cost of ownership analysis and incumbent technology comparison;Kurtz,2014
4. Warid Pakistan expects to save more than US$ 6 million per year after trialling energy efficiency solutions,2014
5. Pakistan telecom trial validates ElectraGen backup power benefits;Fuel Cells Bull,2014