\begin{circus}
\circchannel a, b, c
\end{circus}
\begin{circus}
\circprocess P \circdef \circbegin
\end{circus}
\begin{circusaction}
\circspot
a \then \Skip
\end{circusaction}
\begin{circus}
\circend
\end{circus}
\begin{circus}
\circprocess Q \circdef \circbegin
\end{circus}
\begin{circusaction}
\circspot
a \then b \then \Skip
\end{circusaction}
\begin{circus}
\circend
\end{circus}
\begin{circus}
\circprocess R \circdef \circbegin
\end{circus}
\begin{circusaction}
\circspot
a \then b \then c \then\Skip
\end{circusaction}
\begin{circus}
\circend
\end{circus}
\begin{circus}
\circprocess MS \circdef (P \lpar \lchanset a, b, c \rchanset \rpar Q) \lpar \lchanset a, b, c \rchanset \rpar R
\end{circus}