https://publications.opengroup.org/
The Open Group Library
The Open Group Library offers a wide range of publications including standards, guides, webinars, white papers, and more. You can browse by category, or...
the open grouplibrary
https://www.unix.org/
UNIX® - A Standard of The Open Group
The Open Group holds the UNIX trademark in trust for the industry, and manages the UNIX trademark licensing program.
the open groupstandard