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Douglas Massey , a professor of sociology at Princeton University who heads the Mexican Migration Project , says that tougher border controls are changing the nature of illegal immigration .
 person of company: Douglas Massey, Princeton University
Given options, please tell me the relationships of all the listed entity pairs.Output format is "relation1: word1, word2; relation2: word3, word4". 
Option: ethnicity, place lived, geographic distribution, company industry, country of administrative divisions, administrative division of country, location contains, person of company, profession, ethnicity of people, company shareholder among major shareholders, sports team of location, religion, neighborhood of, company major shareholders, place of death, nationality, children, company founders, company founded place, country of capital, company advisors, sports team location of teams, place of birth 
Text: {0} 
 Entity Pairs:  Douglas Massey, Princeton University 
Answer:
 person of company: Douglas Massey, Princeton University