\begin{tabbing}
R{-}base{-}domain($R$)
\\[0ex]$\,\equiv$$_{\mbox{\scriptsize def}}$$\;\;$es\_realizer\_ind(\=$R$;\+
\\[0ex]$<$0, $\cdot>$;
\\[0ex]${\it left}$,${\it right}$,${\it rec}_{1}$,${\it rec}_{2}$.$<$0, $\cdot>$;
\\[0ex]${\it loc}$,$T$,$x$,$v$.$<$1, $x$$>$;
\\[0ex]${\it loc}$,$T$,$x$,$L$.$<$2, $x$$>$;
\\[0ex]${\it lnk}$,${\it tag}$,$L$.$<$3, ${\it lnk}$, ${\it tag}$$>$;
\\[0ex]${\it loc}$,${\it ds}$,${\it knd}$,$T$,$x$,$f$.$<$4, ${\it knd}$, $x$$>$;
\\[0ex]${\it ds}$,${\it knd}$,$T$,$l$,${\it dt}$,$g$.$<$5, ${\it knd}$, $l$$>$;
\\[0ex]${\it loc}$,${\it ds}$,$a$,$T$,$P$.$<$6, $a$$>$;
\\[0ex]${\it loc}$,$k$,$L$.$<$7, $k$$>$;
\\[0ex]${\it loc}$,$k$,$L$.$<$8, $k$$>$;
\\[0ex]${\it loc}$,$x$,$L$.$<$9, $x$$>$)
\-
\end{tabbing}