title: LaTeX: How to find package(s) that a command belongs to?
body: <p>It is a simple question to which I am not able to find the answer:</p>
  
  <p>Given a LaTeX <strong>command</strong>, how do I find out what <strong>package</strong>(s) it belongs to or comes from?</p>
  
  <p>For example, given the <code>\qquad</code> horizontal spacing command, what package does it come from? Especially troublesome since it works without including any package!</p>