The Open Group Book Store
You can browse by subject, type, title, catalog number, ISBN, latest titles, popular titles, electronic publications (downloads), publications freely available, and publications free to members. To quickly find a specific publication, you can find it through our item search.
Most of our publications are available electronically, some are also available in hard cover or CD-ROM format.
You can order hardcopy publications from our worldwide publisher, Van Haren Publishing, and its distributors.A discount of 15% is available for employees of members of The Open Group if ordering direct from Van Haren through the web.
If you have already registered at the Van Haren store, you can update your profile through "My Account".
When registering at their site, Open Group members should select the tick box to obtain a 15% discount on all book orders as in this screenshot 
Go to Van Haren