News Sources that can be accessed on the open web, along with links to their editorial policies and codes of ethics: (note where these fall on the Media Bias Chart).
The newspapers listed below are widely considered national newspapers of record, with links to their editorial policies and codes of ethics:
New York Times Standards and Ethics
Wall Street Journal Newsroom Standards & Ethics
LAT Newsroom Ethics Guidelines
The Washington Post Policies and Standards
According to Michael Caulfield's Web Literacy for Student Fact-Checkers, these papers are "distinguished" in two ways: "They are rigorous, showing attention to detail and having accountability in their editorial processes." AND "They have a truly national view and attempt to be the best possible record of what happened in the nation (not just a region) on a given day."
"National Newspapers of Record." Web Literacy for Student Fact-Checkers, 2017. Press Books. Accessed 13 Aug. 2018.