Added index entries.
diff --git a/Doc/ext/extending.tex b/Doc/ext/extending.tex
index 2c0900e..783137a 100644
--- a/Doc/ext/extending.tex
+++ b/Doc/ext/extending.tex
@@ -592,6 +592,8 @@
 \section{Extracting Parameters in Extension Functions
          \label{parseTuple}}
 
+\ttindex{PyArg_ParseTuple()}
+
 The \cfunction{PyArg_ParseTuple()} function is declared as follows:
 
 \begin{verbatim}
@@ -937,6 +939,8 @@
 \section{Keyword Parameters for Extension Functions
          \label{parseTupleAndKeywords}}
 
+\ttindex{PyArg_ParseTupleAndKeywords()}
+
 The \cfunction{PyArg_ParseTupleAndKeywords()} function is declared as
 follows: