%0 Journal Article %A Sergio Invernizzi %A Fabio Zanolin %T On the Existence and Uniqueness of Periodic Solutions of Differential Delay Equations. %J Mathematische Zeitschrift %D 1978 %P 25-38 %V 163 %I mathdoc %U http://geodesic.mathdoc.fr/item/MZ_1978__163_172738/ %F MZ_1978__163_172738