^2 \sin^2\theta} \frac{\partial^2 f}{\partial \phi^2}\]</div>
<p>You can add a link to equations like the one above <a class="reference internal" href="#equation-this-is-a-label">(1)</a> by using <code class="docutils literal notranslate"><span class="pre">:eq:</span></code>.</p>
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<h2><a class="toc-backref" href="#id36"><span class="section-number">3.3. </span>Meta</a><a class="headerlink" href="#meta" title="Permalink to this headline">¶</a></h2>
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