Uniform Title Memorandum of Understanding between the Government of the United States of America and the Government of the Hellenic Republic Concerning the Imposition of Import Restrictions on Categories of Archaeological and Byzantine Ecclesiastical Ethnological Material through the 15th Century A.D. of the Hellenic Republic (2011 July 17). Protocols, etc. (2016 November 18) Title Cultural exchanges, property, and cooperation : agreement between the United States of America and Greece, agreement to extend the Memorandum of Understanding of July 17, 2011, effected by exchange of notes at Athens, November 18, 2016; entered into force November 5, 2019 with effect from November 21, 2016.