Facebook CEO Mark Zuckerberg says the company is working with fact-checking organizations to put in place third-party verification of the authenticity of news on its site. Zuckerberg said the website needs to be careful not to discourage sharing of opinions or restrict accurate content. The percentage of misinformation on the site is relatively small, Zuckerberg wrote, echoing his previous view of the issue. The company is focusing on better technical systems for the detection of false news even before people flag them as fakes, Zuckerberg said.”]