I'm pretty sure the Wall Street Journal always includes a disclosure about ownership in any stories mentioning Murdoch, but I need to check.
I've just this moment found a good model for disclosure in a blog post at The New Yorker:
An earlier version of this post did not disclose the author’s relationships with some sources whose research he cites. Gabriele Oettingen is a professor at New York University, where the author also teaches. Heather Barry Kappes is a former student of the author’s, with whom he has collaborated. The post has been updated to reflect this.