1. Council Directive 96/48/EC – 23 July 1996 on The interoperability of the trans-European high-speed rail system, Official Journal L 235, October 17, 1996.
2. Commission Decision 2002/731/EC 30 May 2002 on The technical specification for interoperability relating to the control-command and signaling subsystem of the trans-European high-speed rail system, Official Journal L 245, October 12, 2002.
3. Harmonic resonances in railway systems electrified at 2×25kV–50Hz;Ciaccio,1996
4. A simulation model of audio-frequency track circuits;Falvo,2005
5. An audio frequency model of a 2×25kV traction line for high speed railway systems;Bartoni,2005