Documental research by Mascarenhas Barreto of the documents of the man America knows as Cristopher Columbus, and conclusions that Cristovam Colom was after all a Portuguese noble acting as a Secret Agent for King Dom Joao II of Portugal, instead of the fabricated Italian wool or silk weaver with no instruction or education.
The incongruence in the official Hystory is so big, that this book was a must raed in the early 90's.