# zbMATH — the first resource for mathematics

 46L05 General theory of $$C^*$$-algebras 47L30 Abstract operator algebras on Hilbert spaces 41A65 Abstract approximation theory (approximation in normed linear spaces and other abstract spaces) 47B10 Linear operators belonging to operator ideals (nuclear, $$p$$-summing, in the Schatten-von Neumann classes, etc.) 47G10 Integral operators