
\setlength{\unitlength}{1.0in}
\begin{picture}(6,1.5)
	\put(0,0){\framebox(6,1.5)}

	\put(0.25, 0.70){$0$}
	\put(0.50, 0.70){\line(1,0){1.00}}  % horiz line 0 -> A
	\put(0.95, 0.80){$\phi_{0A}$}

	\put(1.45, 1.10){$A$}
	\thicklines
	\put(1.50, 0.40){\line(0,1){0.60}}  % vert line at A
	\thinlines
	\put(1.50, 1.00){\line(1,0){1.00}}  % upper  horiz line A -> B
	\put(1.50, 0.70){\line(1,0){1.00}}  % middle horiz line A -> B
	\put(1.50, 0.40){\line(1,0){1.00}}  % lower  horiz line A -> B
	\put(1.95, 1.20){$\phi_{AB}$}

	\put(2.45, 1.25){$B$}
	\thicklines
	\put(2.50, 0.20){\line(0,1){1.00}}  % vert line at B
	\thinlines
	\put(2.50, 1.20){\line(4,-1){1.00}} % upper  line B -> C
	\put(2.50, 0.70){\line(1,0){1.00}}  % middle horiz line B -> C
	\put(2.50, 0.20){\line(4,1){1.00}}  % lower  line B -> C
	\put(2.95, 1.20){$\phi_{BC}$}

	\put(3.45, 1.10){$C$}
	\thicklines
	\put(3.50, 0.45){\line(0,1){0.50}}  % vert line at C
	\thinlines
	\put(3.50, 0.95){\line(4,-1){1.00}} %
	\put(3.50, 0.70){\line(1,0){1.00}}  % middle horiz line C -> 0
	\put(3.50, 0.45){\line(4,1){1.00}}  %
	\put(3.95, 0.90){$\phi_{C0}$}

	\put(4.65, 0.70){$0$}

\end{picture}
