Tài liệu tham khảo WikiPedia: Tiếng_Igbo http://www.columbia.edu/itc/mealac/pritchett/00fwp... http://www.rogerblench.info/Language/Niger-Congo/V... http://glottolog.org/resource/languoid/id/nucl1417 http://ig.kasahorow.org/app/d http://www.sil.org/iso639-3/documentation.asp?id=i... https://books.google.com/books?id=FXVkAAAAMAAJ&pg=... https://books.google.com/books?id=GqxTrl3x_vgC&pg=... https://www.idref.fr/027458881 https://id.loc.gov/authorities/subjects/sh85064203 https://d-nb.info/gnd/4120202-8
