THE CONSTITUTION OF THE REPUBLIC OF COSTA RICA
TITLE I - THE REPUBLIC
ARTICLE 7. Public treaties, international agreements and concordats duly approved by the Legislative Assembly shall have a higher authority than the laws upon their enactment or from the day that they designate.
Public treaties and international agreements referring to the territorial integrity or the political organization of the country shall require the approval of the Legislative Assembly by a vote of not less than three fourths of its total membership and the approval of two-thirds of the Members of a Constitutional Assembly called for the purpose .
EDIT.