Council Directive 89/438/EEC of 21 June 1989 amending Directive 74/561/EEC on admission to the occupation of road haulage operator in national and international transport operations, Directive 74/562/EEC on admission to the occupation of road passenger transport operator in national and international transport operations and Directive 77/796/EEC aiming at the mutual recognition of diplomas, certificates and other evidence of formal qualifications for goods haulage operators and road passenger transport operators, including measures intended to encourage these operators effectively to exercise their right to freedom of establishment