<https://freakonomics.com/2010/09/09/puzzler-on-prom-dresses-and-textbooks/>
<http://schema.org/url>
<https://freakonomics.com/2010/09/09/puzzler-on-prom-dresses-and-textbooks/>
<https://freakonomics.com/2010/09/09/puzzler-on-prom-dresses-and-textbooks/>