 $$\RF(00) =  \left( \begin{array}{cccc} -0 & 0 & 0 & 0\\0 & -0 & 0 & 0\\ 0 & 0 & -0 & 0 \\ 0 & 0 & 0 & -0  \end{array}\right), \quad {\mbox{\rm and}}  \;  \RF(00) =  \left( \begin{array}{cccc} -0 & 0 & 0 & 0\\0 & -0 & 0 & 0\\ 0 & 0