<http://schema.org/target>
"https://mobile.audible.com/search.htm?keywords={search_term_string}"^^<http://www.w3.org/2001/XMLSchema#string>
<https://mobile.audible.com/pd/Radio-TV/To-the-Best-of-Our-Knowledge-Doing-the-Math-Updated-Audiobook/B00UCGO7M4>