  Let $F_p$ be the field of a prime order $p$. Then for any positive integer
$n>1$, for any $\epsilon>0$, and for any subset $A$ of $F_p$, every element of
$F_p$ can be represented as a sum of $N$ elements, each of them is a product of
$n$ elements from $A$, where $N$ depends on $n$ and $\espilon$.
