EntityQ3105146· pop 7· linked from 68 articlesexotic sphereSign in to savesmooth manifold that is homeomorphic but not diffeomorphic to a sphereConnectionshomeomorphismEntitydiffeomorphismEntitycobordismEntityBrieskorn manifoldEntityInternational Standard Book NumberEntitydigital object identifierEntityInternational Standard Serial NumberEntityderivativeEntityGrigori PerelmanEntityquaternionEntityQ180686EntityJSTOREntitybibcodeEntityQ118398Entityabelian groupEntitymanifoldEntityQ229883EntityPoincaré conjectureEntitymonoidEntityJohn MilnorEntityCategoriesDifferential structuresDifferential topologySpheresSurgery theory