PageHeader : Funkcialaj Ekvacioj, 36 (1993) 71-93 Title : Retarded Functional Differential Equations Title : with $L^{1}-$ Valued Controller AuthorInfo : By AuthorInfo : Jin-Mun JEONG AuthorInfo : (Osaka University, Japan) section : 1. Introduction section : 2. Notations section : 3. Elliptic boundary value problem in $W^{-1,p}$ section : 4. Retarded functional differential equations and structural operators section : 5. Controllability and observability section : References