diff --git a/first.tex b/first.tex
index 126fd6a..8853eb4 100644
--- a/first.tex
+++ b/first.tex
@@ -118,7 +118,8 @@ \subsection*{Acknowledgments}
 
 The subset of Scheme in
 {\em The Little Schemer}~\cite{LittleSchemer} provided inspiration for
-Pico Scheme. We would like to thank Masanori Ogino for help with the Pico Scheme Report.
+Pico Scheme. We would like to thank Masanori Ogino and Wolfgang Corcoran-Mathe
+for help with the Pico Scheme Report.
 
 
 \todo{expand the summary so that it fills up the column.}
diff --git a/sem.tex b/sem.tex
index 47eeddb..4f26968 100644
--- a/sem.tex
+++ b/sem.tex
@@ -155,13 +155,13 @@ \subsection{Semantic functions}
 \begin{semfun}
   \Esem\sembrack{\hbox{\texttt{(lambda (\arbno{\I}) \arbno{\D} $\E_0$)}}} =$\\
   \go{1}\=$\lambda\rho\:.\:(\lambda\arbno{\epsilon}\:.\:\#\arbno{\epsilon} = \#{\arbno{\I}}\rightarrow$\\
-  \>\go{1}$(\Esem\sembrack{E_0})((tiedecs\:\Esem\sembrack{\arbno{\D}})(extends\:\rho\:\arbno{\I}\:\arbno{\epsilon})),$\\
+  \>\go{1}$(\Esem\sembrack{E_0})((tiedecs\:(extends\:\rho\:\arbno{\I}\:\arbno{\epsilon})\:\Dsem\sembrack{\arbno{\D}})),$\\
  \>\go{1}$ \wrong{wrong number of arguments})
 \end{semfun}
 
 \begin{semfun}
   \Esem\sembrack{\hbox{\texttt{(lambda \I \: \arbno{\D} $\E_0$)}}} =$\\
-  \go{1}\=$\lambda\rho\:.\:(\lambda\arbno{\epsilon}\:.\:(\Esem\sembrack{E_0})((\fun{tiedecs}\:\Esem\sembrack{\arbno{\D}})(\rho[\langle\arbno{\epsilon}\rangle/\I])))
+  \go{1}\=$\lambda\rho\:.\:(\lambda\arbno{\epsilon}\:.\:(\Esem\sembrack{E_0})((\fun{tiedecs}\:(\rho[\langle\arbno{\epsilon}\rangle/\I])\:\Dsem\sembrack{\arbno{\D}})))
 \end{semfun}
 
 \begin{semfun}