\begin{tikzpicture}
	\begin{pgfonlayer}{nodelayer}
		\node [style=red node] (0) at (0, 1) {};
		\node [style=blue node 2] (1) at (1, 0) {};
		\node [style=blue node] (2) at (-1, 0) {};
		\node [style=yellow square] (3) at (0, -1) {\param{\alpha}};
	\end{pgfonlayer}
	\begin{pgfonlayer}{edgelayer}
		\draw [in=-90, out=0] (3) to (1);
		\draw [bend right] (3) to (2);
		\draw (2) to (0);
		\draw (0) to (1);
	\end{pgfonlayer}
\end{tikzpicture}