Exchange of Letters constituting an Agreement between the Kingdom of the Netherlands, on behalf of Sint Maarten, and the United Nations Educational, Scientific and Cultural Organization (UNESCO) concerning the tenth session of the Intergovernmental Oceanographic Commission (IOC) Intergovernmental Coordination Group for the Tsunami and other Coastal Hazards Warning System for the Caribbean and Adjacent Regions (ICG/CARIBE EWS-X), Philipsburg, Sint Maarten, from 19 to 21 May 2015