Heppell, M. How to Retire 10 Years Early: Your Plan for Less Work and More Life. Pearson Education UK.
Chicago-referens (17:e uppl.)Heppell, Michael. How to Retire 10 Years Early: Your Plan for Less Work and More Life. Pearson Education UK.
MLA-referens (8:e uppl.)Heppell, Michael. How to Retire 10 Years Early: Your Plan for Less Work and More Life. Pearson Education UK.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.