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Singapore  's  Nanyang Technological University  ( NTU ) and the Geneva-based International Air Transport Association ( IATA ) on Tuesday signed a Memorandum of Understanding ( MOU ) to collaborate on the development and upgrading of human capital for the global aviation industry .
 country of headquarters: Singapore, Nanyang Technological University
Given a phrase that describes the relationship between two words, extract the words and the lexical relationship between them. The output format should be "relation1: word1, word2; relation2: word3, word4". 
Option: cities of residence, top members employees, members, alternate names, origin, state or provinces of residence, title of person, spouse, city of headquarters, NA, founded by, state or province of headquarters, employee of, countries of residence, country of birth, founded, subsidiaries, country of headquarters 
Text: {0} 
Answer:
 country of headquarters: Singapore, Nanyang Technological University