<https://booktree.ng/signal-in-the-dark-by-mildred-augustine-wirt-pdf/#primaryimage>
<http://schema.org/height>
"330"^^<http://www.w3.org/2001/XMLSchema#integer>
<https://booktree.ng/signal-in-the-dark-by-mildred-augustine-wirt-pdf/>