<ul><li><a href=https://dre.pt/dre/legislacao-consolidada/decreto-lei/1996-70300359 target=_blank>Decree-Law 176/96 on the fixed price of books(Decreto-Lei que aprova o Código do Procedimento Administrativo,  Adopted 07/01/2015, last amended 15/12/2021, Articles 2 and 4)</a></li></ul>