Characterizations of Jordan derivations on triangular rings: additive maps Jordan derivable at idempotents. An, Runling, Hou, Jinchuan (2010) ELA. The Electronic Journal of Linear Algebra [electronic only]
Completely 1-complemented subspaces of the Schatten spaces S p Jean Roydor (2007) Banach Center Publications We describe the subspaces of S p (1 ≤ p ≠ 2 < ∞) which are the range of a completely contractive projection.