diff --git a/programming/lecture/programming.tex b/programming/lecture/programming.tex
index e05e381..44c025e 100644
--- a/programming/lecture/programming.tex
+++ b/programming/lecture/programming.tex
@@ -362,8 +362,8 @@ number of elements irrespective of the type of vector.
 Listings~\ref{vectorelementslisting} and~\ref{vectorrangelisting} show
 how the index is used to access elements of a vector. One can access
 individual values by providing a single index or use the
-\code[Operator!Matrix!:]{:} notation to access multiple values with a
-single command.
+\code[Operator!Matrix!:]{:} operator to access multiple values with a
+single command (see also the info box below \ref{important:colon_operator}).
 
 \begin{lstlisting}[label=vectorelementslisting, caption={Access to individual elements of a vector.}]
 >> a = (11:20)
@@ -403,13 +403,14 @@ ans =
 \end{exercise}
 
 \begin{important}[The : (colon) operator]
+  \label{important:colon_operator}
   The colon \code[Operator!colon@:]{:} operator is often used when working with vectors. It has multiple purposes.
   \begin{enumerate}
     \item In the simplest form,  \code{x = a:b} with \code{a} and \code{b} being two numbers, it creates 
   a vector \code{x} containing the numbers \code{a} to \code{b} in integer steps. In \matlab{} the borders $a$ and $b$ are included $[a, b]$ or $a\leq x \leq b$.
-    \item In the form \code{x = a:c:b} the vector \code{x} uses a \emph{stepsize} of \code{c} to create the range of numbers.
+    \item In the form \code{x = a:c:b} the vector \code{x} uses a \emph{stepsize} of \code{c} to create the range of numbers ranging from $a$ to $b$ in steps of $c$.
     \item When used in the context of indexing such as \code{x(:)} all elements of the vector x are accessed.
-    \item As vectors are often used for indexing in other vectors one use the colon operator to create such vectors implicitely, e.g. \varcode{x(1:2:end)} to access every seond element of \code{x}. 
+    \item Vectors are often used for indexing in other vectors. To do so the colon operator is used to create such vectors implicitely, e.g. \varcode{x(1:2:end)} to access every second element of \code{x}. 
   \end{enumerate}  
 \end{important}