In the context of the study of symmetry, Atractor developed GeCla program (for Mac and Windows) and it can be downloaded for free:
Unlike previous versions, the new version of GeCla does not require prior installation of Atractor's DVD, which simplifies the installation process.
We strongly advise you to always use the latest version of GeCla (specially in competition mode).
Version beta 1.01 - 2016/10/06
Languages presently supported: (Soon:)
(++) See Use of Atractor's materials