Intelligent design start 

re your wondering "I don't know exactly which sources would be free of such potential bias", and suggested sources ...
responding here since what I've to say isn't on the threads topic...  I've got two thoughts on bias

1. We don't need to  just use the cites.  I think defining ID should not be our creatively editing, nor taking from a outside source, but rather should present just cite to fact of what the origination/definition was/is without worrying over if they are right, wrong or motives  otherwise we've not presented that position in way that can avoid adding color, and have no basis cite that seems defensible.. 

2. I think the article is unrecoverably biased, but meh  since it's fairly obvious that it is so mitigates the issue.  It is also a bit better yet if a statement is cited  if the source is clearly one side or the other then makes things clearer to the reader.
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