title: R bookdown - custom title page
body: <p>How to customize title page using bookdown?</p>
  
  <p>I tried using the following code in the YAML header.</p>
  
  <pre><code>includes:
    in_header: preamble.tex
    before_body: body.tex
  </code></pre>
  
  <p>The body.tex file was something pretty simple, just for test:</p>
  
  <pre><code>\begin{titlepage}
  Hello world
  \end{titlepage}
  </code></pre>