  A signified graph is a pair $(G, \Sigma)$ where $G$ is a graph, and $\Sigma$
is a set of edges marked with '$-$'. Other edges are marked with '$+$'. A
signified coloring of the signified graph $(G, \Sigma)$ is a homomorphism into
a signified graph $(H, \Delta)$. The signified chromatic number of the
signified graph $(G, \Sigma)$ is the minimum order of $H$.
  In this paper we show that for every 2-dimensional grid $(G, \Sigma)$ there
exists homomorphism from $(G, \Sigma)$ into the signed Paley graphs $SP_9$.
Hence signified chromatic number of the signified grids is at most 9. This
improves upper bound on this number obtained recently by Bensmail.
