上QQ阅读APP看书，第一时间看更新
Further reading
Alistair Cockburn, Writing Effective Use Cases, Addison-Wesley Professional, 1st Edition, 2000
John Ferguson Smart, BDD in Action, Manning Publications, 1st Edition, 2014
Five whys, https://en.wikipedia.org/wiki/Five_whys
Eric Ries, https://hbr.org/2010/02/entrepreneurs-beware-of-vanity-metrics