The first entry is always the pin's source. Overall confidence is a weighted average of how firmly each reference supports the start and end times used above; a reference counts half as much for every 180 days older than the newest.
Alstom's[3] own press release states the record was "set at 13h13 on 3 April 2007" at 574.8 km/h.
Wikipedia entry on the V150 test train confirms the record specs and the Le Chemin, Marne location.
Alstom's own press release naming the exact time, date, speed and location of the V150 record run.
Something missing or wrong? Say it in your own words: a link that backs this pin up, a different start or end date and why, or a fact it lacks or gets wrong. The AI checks it against this pin's sources, searches for better ones, and adds any page that backs you up. The pin's own sources still count most.