<http://schema.org/query-input>
"required name=search_term_string"^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.audible.com/pd/Bios-Memoirs/The-Voice-That-Challenged-a-Nation-Audiobook/B002V5B0RY/ref=det_sim_narr_3>