https://pressbooks.pub/vacationdata/chapter/-what-days-are-expedia-cheapest/

https://pressbooks.pub/vacationdata/chapter/%f0%9d%95%86%f0%9d%95%8b%f0%9d%94%b8-%f0%9d%9f%a0%f0%9d%9f%98%f0%9d%9f%98what-days-are-expedia-cheapest/