Say When and Where
http://www.webpagecontent.com/arc_archive/164/5/

McAlpine, Rachel
Quality Web Content
2005

Abstract:

Certain expressions in web content get users all discombobulated. Relative expressions of time and place need an anchor, a key, right there in the text. Some common confusers follow. They would not be a problem in other circumstances. But on the Web or intranet, every page must make sense in isolation.