............14-January-2016.................The site was created.

............14-February-2016................The first version of Happy Sloth was loaded.

............06-September-2016...............Happy Sloth was registered in Russian Federal Service for Intellectual Property.

............01-October-2016.................Happy Sloth was presented during XIV International Conference “Mossbauer Spectroscopy and its Applications” in Kazan.

............10-May-2019.....................The new version of Happy Sloth was loaded.

............10-May-2019.....................The last version of Happy Sloth was loaded.

............25-October-2021.................D.M.Levin died

............20 September-2022...............Happy Sloth is not supported anymore. Its full version is available for everyone.

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