Horowitz Ben. (2014). The hard thing about hard things: Building a business when there are no easy answers. HarperCollins.
Chicago-viite (17. p.)Horowitz Ben. The Hard Thing About Hard Things: Building a Business When There Are No Easy Answers. New York: HarperCollins, 2014.
MLA-viite (9. p.)Horowitz Ben. The Hard Thing About Hard Things: Building a Business When There Are No Easy Answers. HarperCollins, 2014.
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