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Issue 258:
\begin{equation}\label{eq:1}
\begin{split}
x &= y \\
& z
\end{split}
\end{equation}

\begin{equation}\label{eq:2}
\begin{split}
a &= b \\
& q
\end{split}
\end{equation}


Issue 109: 
\begin{align}
\begin{split}
    \dot{x} &= s (y - x)\label{eqn:lorenz}\\
    \dot{y} &= r x - y - x z \\
    \dot{z} &= x y - b z,
\end{split}
\end{align}


\end{document}

