We will be leaving Paris on May 31 heading to Rouen by train (one-way). From reading Rick Steves' France guidebook it isn't clear if advance ticket purchase is recommended for that journey at that time of year on a Friday.
If so do you know if train itineraries shown at Google are reliable? For example I see an 08:53 train from Gare St. Lazare in Paris to Rouen. However SNCF's web site doesn't show that.
Thanks
Sri