Methodology and parameters for the change of reference system approved by the Cartographic Coordination Commission of Catalonia in the meeting of 23rd September 2009.
Instruction to all bodies producing official geoinformation in Catalonia to transform the information in ED50 to ETRS89, approved by the C4 in the meeting of 19th December 2011.
Procedures to establish coordinates in the SPGIC, approved by the C4 in the meeting of 16th June 2016.