1. National Grid: ‘Grid code report’ November2011 pp11/61a
2. National Grid: ‘System operability framework’ September2014
3. National Grid: ‘Electricity ten year statement 2011’. Available atwww.nationalgrid.com/uk/electricity/ten‐year‐statement
4. National Grid: ‘Frequency change during large disturbances and their impact on the total system’.Industry Consultation Report 2013