Coding standards

https://www.drupal.org/docs/develop/standards/coding-standards

https://github.com/djoos/Symfony2-coding-standard

http://symfony.com/doc/current/contributing/code/standards.html

https://www.tiobe.com/static-code-checkers-survey/

https://www.javacodegeeks.com/2012/10/java-code-quality-tools-overview.html

https://en.wikipedia.org/wiki/List_of_tools_for_static_code_analysis

http://www.icsharpcode.net/TechNotes/Commenting20020413.pdf