Open details page in AMP with dynamic data (get query string from url)

Question

I'm starting with AMP - Accelerated Mobile Pages, and I've some doubts according to dynamic JSON data.

I've a amp-list with a JSON retrieved by an API, it works fine, my question is:

How do I open the details page for the list items?

Should I use an a tag like this one?

<a href="details.html?ref={{ref}}">list item</a>

If yes, how do I get the ref token from the URL?