Project Gutenberg was the first provider of free electronic books, or eBooks. Michael Hart, founder of Project Gutenberg, invented eBooks in 1971 and his memory continues to inspire the creation of eBooks and related technologies today.1001 задача для умственного счета by Sergei Aleksandrovich RachinskiiAuthor: Rachinskii, Sergei Aleksandrovich, 1836-1902,Language: Russian, Class: QA: Science: Mathematics, Release Date: Aug 14, 2005