Existence of bases and the dual splitting relation for Fréchet spaces Jörg Krone — 1989 Studia Mathematica
Complemented subspaces with a strong finite-dimensional decomposition of nuclear Köthe spaces have a basis Jörg Krone; Volker Walldorf — 1998 Studia Mathematica The following result is proved: Let E be a complemented subspace with an r-finite-dimensional decomposition of a nuclear Köthe space λ(A). Then E has a basis.