- Clean Language: https://clean.cs.ru.nl/Clean
- Clean Language Documentation: https://clean.cs.ru.nl/Clean
- Cloogle: https://cloogle.org
- CLEAN language report (CLEAN 2.0): https://wiki.clean.cs.ru.nl/download/html_report/CleanRep.2.2_1.htm
- CLEAN language report documentation (CLEAN 2.0): https://cloogle.org/doc/#_3