crisp-theme/_includes/series_list.njk

<nav>
  <h2>{{ seriesName }}</h2>
  <a href="/series/{{ seriesName | slugify }}/">View on one page</a>
  <ol>
  {%- for post in collections.posts | seriesPosts(seriesName) %}
    {% include "post_link.njk" %}
  {%- endfor %}
  </ol>
</nav>