On the geometric properties of Cesàro spaces

It is proved that the Cesàro space $\operatorname{Ces}_{p}[0,1]$, $1\le p<\infty$, contains a complemented subspace isomorphic to $l^q$ if and only if either $q=1$ or $q=p$. A class of subspaces of this space that contain complemented copies of the space $l^p$ is distinguished.
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