\begin{tikzpicture}[node distance=2cm and 2cm,auto] \tikzset{myptr/.style={decoration={markings,mark=at position 1 with % {\arrow[scale=3,>=stealth]{>}}},postaction={decorate}}} \coordinate[] (e1) {}; \node[shape=rectangle, draw, left = of e1] (l1) { \begin{tabular}{l l} Schubert & 1797–1828 \\ Shumann & 1810–1856 \end{tabular} }; \node[shape=rectangle, draw, right = of e1] (r1) { \begin{tabular}{l l} Schubert & Austria \\ Shumann & Germany \end{tabular} }; \draw (l1) -- (e1) -- (r1); \coordinate[below = of e1,label={$\iota_L \rightarrow \iota_R$}] (e2) {}; \node[shape=rectangle, draw, left = of e2] (l2) { \begin{tabular}{l l} Schubert & 1797–1828 \\ Shumann & 1810–1856 \\ \textcolor{blue}{Monteverdi} & \textcolor{blue}{1567–1643} \end{tabular} }; \node[shape=rectangle, draw, right = of e2] (r2) { \begin{tabular}{l l} Schubert & Austria \\ Shumann & Germany \\ \textcolor{red}{Monteverdi} & \textcolor{red}{\emph{null}} \end{tabular} }; \draw[myptr] (l2) -- (e2) |- (r2); \coordinate[below = of e2,label={$\delta_R \leftarrow \delta_L$}] (e3) {}; \node[shape=rectangle, draw, left = of e3] (l3) { \begin{tabular}{l l} Schubert & 1797–1828 \\ \textcolor{red}{Schumann} & 1810–1856 \\ Monteverdi & 1567–1643 \end{tabular} }; \node[shape=rectangle, draw, right = of e3] (r3) { \begin{tabular}{l l} Schubert & Austria \\ \textcolor{blue}{Schumann} & Germany \\ Monteverdi & \textcolor{blue}{Italy} \end{tabular} }; \draw[myptr] (r3) -- (e3) |- (l3); \end{tikzpicture}