Versioning History
This page provides a record of edits and changes made to this book since its initial publication in the Books4Languages. Open Textbook Collection. Whenever edits or updates are made in the text, we provide a record and description of those changes here. If the change is minor, the version number increases by 0.1. If the edits involve substantial updates, the version number increases to the next full number.
The files posted by this book always reflect the most recent version.
| Version | Date | Change | Affected Web Page |
| 1.0 | 2019 | Primary release | Introduction, Form, Example, Use and Summary sections |
| 2.0 | 2020 | Complementary information | Relate content section Exercises Videos and other URLs |
| 2.1 | 2021 | Upgrade, speeling and rephrase as appropriate | Introduction, Form, Examples and Use sections |