RER C

Parisbytrain.com will have one, probably. But you don't really need it. They run every fifteen minutes or so, start at about five and stop maybe a half hour prior to midnignt.

Good enough! Thanks

Here's a link to the Paris RER Map. It's not the schedule but they do run frequently. http://www.paris-tourist-information.co.uk/images/maps/paris-rer-map.pdf Where are you intending to travel on this line? RER C has a couple of different routes. Is it your intention to travel to Versailles? If yes, I have additional info.