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\begin{document}

\begin{center}
{\Large \bf Iterated cyclic homology}
\end{center}

From the viewpoint of rational homotopy theory, we introduce an
 iterated cyclic homology of commutative differential graded algebras 
over the rational field, which is a generalization of 
the ordinary cyclic homology of such algebras. 
Let $\T$ be the circle group and $\F(\T^l, X)$ denote the function space of 
continuous maps from the $l$-dimensional torus $\T^l$ 
to an $l$-connected space $X$. It is also shown that 
the iterated cyclic homology of the differential graded algebra of 
polynomial forms on $X$ is isomorphic to the rational cohomology algebra 
of the Borel space 
$E\T\times_{\T} \mathcal{F}({\T}^l, X)$, 
where the $\T$-action on $\F(\T^l, X)$ is induced by 
the diagonal action of $\T$ on the domain $\T^l$. 

\end{document}
