Citation Hunt

The Wikipedia snippet below is not backed by a reliable source. Can you find one?

Click I got this! to go to Wikipedia and fix the snippet, or Next! to see another one. Good luck!

In page Ulm Hauptbahnhof:

"

Deutsche Bundesbahn modernised the Fils Valley Railway between Stuttgart and Ulm up to 12 October 1981, introducing reversible working of the tracks.[3]