der maa fastsaettes en fremgangsmaade for en loebende tilpasning af skemaerne til bogfoeringen , listen over infrastrukturerne samt listen over de givne data om benyttelsen af infrastrukturerne til den indvundne erfaring og udviklingen i den faelles transportpolitik ;
Whereas provision should be made for a procedure whereby the forms of accounts, the list of types of infrastructure and the schedule of returns concerning the use of infrastructure may be constantly adjusted in the light of experience and of the development of the common transport policy;