4-dimensional c-symplectic S 1 -manifolds with non-empty fixed point set need not be c-Hamiltonian Akio Hattori — 1998 Banach Center Publications The aim of this article is to answer a question posed by J. Oprea in his talk at the Workshop "Homotopy and Geometry".
Almost complex toric manifolds and positive line bundles Akio Hattori — 1998 Banach Center Publications