N CLASS="SPAN">    </SPAN></TD>
<TD CLASS="LEFT"><SPAN CLASS="SPAN">             </SPAN></TD>
<TD CLASS="CENTER"><SPAN CLASS="SPAN">    </SPAN></TD>
<TD CLASS="LEFT"><SPAN CLASS="SPAN">     POTENT </SPAN></TD>
<TD CLASS="CENTER"><SPAN CLASS="SPAN">external potentials</SPAN></TD>
<TD CLASS="LEFT"><SPAN CLASS="SPAN"></SPAN></TD>
<TD CLASS="CENTER"><SPAN CLASS="SPAN"></SPAN></TD>
<TD CLASS="LEFT"><SPAN CLASS="SPAN"></SPAN></TD>
<TD CLASS="LEFT"><SPAN CLASS="SPAN"></SPAN></TD>
<TD CLASS="LEFT"><SPAN CLASS="SPAN