Groot, H. C. (2011). The peace corps - 50 years later: Some personal reminiscences. Bulletin of the American Historical Collection.
Lua i Stíl Chicago (17ú heag.)Groot, Hans C. "The Peace Corps - 50 Years Later: Some Personal Reminiscences." Bulletin of the American Historical Collection 2011.
Lua MLA (9ú heag.)Groot, Hans C. "The Peace Corps - 50 Years Later: Some Personal Reminiscences." Bulletin of the American Historical Collection, 2011.
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