. "k-theory" . . "K-theory" . "''K''-theoretical" . . . . . "complex topological k-theory" . . . "operator K-theory" . . "K-theories" . . "K-theoretic" . "''K''-theory" . . . . . "-Theorie" . "K-groups" . "algebraic" . . "K-theory" . "K-Theory" . "-theory" .