Heppell, M. How to Retire 10 Years Early: Your Plan for Less Work and More Life. Pearson Education UK.
Παραπομπή σε μορφή Chicago (17η εκδ.)Heppell, Michael. How to Retire 10 Years Early: Your Plan for Less Work and More Life. Pearson Education UK.
Παραπομπή σε μορφή MLA (8th εκδ.)Heppell, Michael. How to Retire 10 Years Early: Your Plan for Less Work and More Life. Pearson Education UK.
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