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IP address: 172.70.127.149
Time: 2024-11-19T17:46:19Z
URL: https://scholar.google.com/scholar_lookup?author=Campbell%2C+D.F.&publication_year=2005&title=Dise%C3%B1os+Experimentales+y+Cuasiexperimentales+en+la+Investigaci%C3%B3n+Social