The Ghent Workgroup has published a Guideline for the GWG 2015 PDF/X workflow. The publication is based on the PDFX-ready Guideline.

There are dutch and english translation available at the moment.

In addition there is a dutch and an english sample page.

In the Ghent version of the guideline only the first part of the PDFX-ready guideline was considered. Unfortunately important topics like PDF preflight and output workflow are missing.