His first book of poetry from 1969, "Sobre la marcha" ("On the March"), contains one of the most iconic Dominican poems of the twentieth century, “The Immigrants.”[5] The books of poetry to follow in later years, beginning with "La Urdimbre de Silencio", ("At the Threshold of Silence)" offer a wide-ranging reflection on the world beyond the island of his birth, voiced with the poignant longing of an expatriate.[6]