<ul><li><a href=https://diariodarepublica.pt/dr/detalhe/decreto-lei/257-2007-636181 target=_blank>Decree-Law 257/2007 regulating the activity of road freight transport(Decreto-Lei  do regime jurídico da actividade de transporte rodoviáriode mercadorias, Adopted 16/07/2007, Last modification 05/06/2009, Article 9)</a></li><li><a href=http://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX%3A31989R4058 target=_blank>Council Regulation (EEC) 4058/1989 on the fixing of rates for the carriage of goods by road between Member States(Regulamento (CEE) relativo à formação dos preços para o transporte rodoviário de mercadorias entre os Estados- membros, Adopted 21/12/1989, Articles 1 and 2)</a></li></ul>