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Romeiras, Maria M.; Cotrim, Helena C.; Duarte, Maria C.; Pais, Maria S. (2007). "Genetic diversity of three endangered species of Echium L. (Boraginaceae) endemic to Cape Verde Islands". Biodiversity and Conservation. 16 (2). Springer: 547–566. doi:10.1007/s10531-006-6734-0. S2CID24503703.
semanticscholar.org
api.semanticscholar.org
Romeiras, Maria M.; Cotrim, Helena C.; Duarte, Maria C.; Pais, Maria S. (2007). "Genetic diversity of three endangered species of Echium L. (Boraginaceae) endemic to Cape Verde Islands". Biodiversity and Conservation. 16 (2). Springer: 547–566. doi:10.1007/s10531-006-6734-0. S2CID24503703.
tela-botanica.org
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