Changes made by Commission Decision of 21 February 2011 setting the European Union-wide performance targets and alert thresholds for the provision of air navigation services for the years 2012 to 2014 (2011/121/EU)
EU Decision 2011/121
No changes made by Commission Decision of 21 February 2011 setting the European Union-wide performance targets and alert thresholds for the provision of air navigation services for the years 2012 to 2014 (2011/121/EU) are recorded.
From legislation.gov.uk's record of changes, the official one: see it there.