Gruber, Ruth
Puerto Rico: island of promise
Hill and Wang, 1960
 Buku Teks SO
Galbraith, John Kenneth, 1908-2006
Marketing efficiency in Puerto Rico
Harvard University Press, 1955
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Steel, Danielle
The promise : a novel
A Dell Book, 1984
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Friedrich, Carl J.
Puerto Rico : middle road to freedom
Rinehart, 1959
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Hanson, Earl Parker
Transformation : the story of modern Puerto Rico
Simon and Shuster, 1955
 Buku Teks SO