Rosero Bixby, L. (2008). The exceptionally high life expectancy of Costa Rican nonagenarians.
Chicago Style aipamenaRosero Bixby, Luis. The Exceptionally High Life Expectancy of Costa Rican Nonagenarians. 2008.
MLA aipamenaRosero Bixby, Luis. The Exceptionally High Life Expectancy of Costa Rican Nonagenarians. 2008.
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