Walker WE, Baarse G, Velzen A van, Järvi T. Assessing the Variation in Rail Interoperability in 11 European Countries, and Barriers to its Improvement. EJTIR [Internet]. 2009 Jan. 1 [cited 2024 May 5];9(1). Available from: https://journals.open.tudelft.nl/ejtir/article/view/3283