title: Latex Problem: Undefined control sequence when using /multirow
body: <p>I simple want to combine some cells in a row of a table in Latex. For instance,
  I tried to compile the following table:</p>
  
  <pre><code>\begin{tabular}{|l|l|l|}  
  \hline  
  \multicolumn{3}{|c|}{Team sheet} \\  
  \hline  
  Goalkeeper &amp; GK &amp; Paul Robinson \\ \hline  
  \multirow{4}{*}{Defenders} &amp; LB &amp; Lucus Radebe \\  
   &amp; DC &amp; Michael Duberry \\  
   &amp; DC &amp; Dominic Matteo \\  
   &amp; RB &amp; Didier Domi \\ \hline  
  \multirow{3}{*}{Midfielders} &amp; MC &amp; David Batty \\  
   &amp; MC &amp; Eirik Bakke \\  
   &amp; MC &amp; Jody Morris \\ \hline  
  Forward &amp; FW &amp; Jamie McMaster \\ \hline  
  \multirow{2}{*}{Strikers} &amp; ST &amp; Alan Smith \\  
   &amp; ST &amp; Mark Viduka \\  
  \hline  
  \end{tabular}  
  </code></pre>
  
  <p>Then I get the error:</p>
  
  <pre><code>! Undefined control sequence.  
  &lt;recently read&gt; \multirow  
  
  l.821 \multirow
  </code></pre>
  
  <p>Does anyone have an idea what I am doing wrong? Do I need a special package? Interestingly enough, the multicolumn command is working! Weird.</p>