k">expression</a></span><span class="op">(</span><span class="fu"><a href="https://rdrr.io/r/base/paste.html" class="external-link">paste</a></span><span class="op">(</span><span class="va">delta</span><span class="op">^</span><span class="fl">15</span>, <span class="st">"N (per mille)"</span>, sep <span class="op">=</span> <span class="st">""</span><span class="op">)</span><span class="op">)</span>,</span>
<span>  title <span class="op">=</span> <span class="st">"Isospace plot of Inger et al Geese data"</s