Fonte:
http://www.dgci.min-financas.pt/NR/rdonlyres/A1566458-CAD9-4227-A448-5404647320DD/0/OfCirc60062.pdfhttp://www.dgci.min-financas.pt/NR/rdonlyres/A1566458-CAD9-4227-A448-5404647320DD/0/OfCirc60062.pdf
