Labour Leadership 2016

Methodologically it's an interesting question. Try tweeting the authors? But I'm not sure how not reporting one paper could be considered bias. Explain? Assuming Times reporting is perfectly neutral it doesn't change the results from the other papers.

I'm wondering why the Times isn't featured

Perhaps the authors didn't want to pay their subscription? :)

They may have seen it as a methodological problem if one paper is behind a paywall, but the others aren't. I assume they didn't buy any of the other papers' paper editions but monitored the web-sites only; perhaps it would have got too expensive to do the study if they'd paid for paper editions and paywall access. Just speculating, I have no idea what the real reason is.