External Sources of Copy

Hi -

Apologies for all of the questions, but I had some concerns about content
reuse on the page I'm editing:
http://docs.webplatform.org/wiki/css/properties/clear which I signed up for
last web platform wednesday but discovered someone else had already filled
out the content.

A large portion of the content from:
https://developer.mozilla.org/en-US/docs/Web/CSS/clear, and I think some of
the other content is from Microsoft.

It's my understanding that since web platform is associated with the w3c,
reusing content from there is okay, but it seems somewhat dubious to me to
take content word for word from mozilla and microsoft. There is an
attribution at the bottom:

"*This article contains content originally from external sources.*

Portions of this content come from the Mozilla Developer Network [image:
cc-by-sa-small-wpd.svg] <http://creativecommons.org/licenses/by-sa/3.0/us/>
: Article <https://developer.mozilla.org/en-US/docs/CSS/clear>

Portions of this content come from the Microsoft Developer Network: Windows
Internet Explorer API reference
Article<http://msdn.microsoft.com/en-us/library/ie/hh828809%28v=vs.85%29.aspx>
"
But to me, attributions like that should only be used for quoted sections,
not the majority of a documents copy. What is the policy on this for web
platform?

Thanks,
Sarah