In my current project, we have an ongoing discussion about whether or not it's a good idea to include an artifact representing a web page in an UML sequence diagram for a web application, making explicit which page starts a business interaction.

I think it's a bad idea to include a web page, for me a sequence diagram should be about business logic and the interactions between business objects, and not include presentation concerns such as web pages. If I were to include a web page it'd be in a navigation diagram. Also, in my experience I had not seen web pages included in sequence diagrams, up until now.

What's the recommendation/best practice on this? Should we include an artifact representing a web page in each of our sequence diagrams, or not?

EDIT :

It'd be ideal if the answers quoted design/modeling guidelines, books on UML, etc. arguing in favor or in opposition to including presentation artifacts in UML design diagrams. So far I haven't found an authoritative source that I can quote on the subject, instead of personal opinions.