| title | ISBN-13 | year of publication |
|---|---|---|
| Principles of Economics V1.1 | 978-1-4533-1205-6 | 2014 |
| Principles of Economics, v. 2.0 | 978-1-4533-5235-9 | 2012 |
| Principles of Macroeconomics | 978-1-4533-2988-7 | 2011 |
| Principles of Macroeconomics, v. 2.0 | 978-1-4533-5157-4 | 2012 |
| Principles of Macroeconomics, Version 2.0 | 978-1-4533-3267-2 | 2012 |
| Principles of Microeconomics Version 1.0.1 | 978-1-4533-5631-9 | 2012 |