The phrase "a known authority" is correct and usable in written English.
It can be used when referring to someone who is recognized as an expert or reliable source in a particular field or subject.
Example: "According to a known authority in climate science, immediate action is necessary to combat global warming."
Alternatives: "a recognized expert" or "a reputable source".
I picked up a rock and that was enough — the creature ran off into the stand of bamboo that bordered the back yard of our neighbor, Dr. Sondervan, who was a psychiatrist, and a known authority on Down syndrome and other genetic misfortunes.
I picked up a rock and that was enough the creature ran off into the stand of bamboo that bordered the back yard of our neighbor, Dr. Sondervan, who was a psychiatrist, and a known authority on Down syndrome and other genetic misfortunes.
That position is "twaddle," said Geoffrey C. Hazard, a nationally known authority on legal ethics at Yale Law School.
The Steve Jobs, so confident as a businessman and technologist, had melted away, and he was asking me – hardly a noted known authority on such things – about his date.
In 1948, Mr. Schreiber, already a nationally known authority on mass transit, was appointed general manager of the Third Avenue Transit Corporation which was bankrupt and carried 1.8 million riders a day in Manhattan, the Bronx and lower Westchester.
Koubek was a nationally known authority on how to draft construction documents for commercial buildings.
The guide must describe in detail: the defined target audience from step one, the format of the electronic files, submittal guidelines, and the writing style to follow (including the reference to a well known authority writing manual that the whole group should follow).
Ron Brachman is an internationally known authority on Artificial Intelligence and Computer Science.
Associate Technical Director for Systems Development and Engineering at Picatinny Arsenal, he was an internationally- known authority in the research and development of armaments.
The Princetonians were joined by a group of about 20 passengers from the Harvard Museum of Natural History, led by James McCarthy, professor of biological oceanography at Harvard, an internationally known authority on the science of climate change, and 50 to 60 unaffiliated travelers.
Scott McKain, founder of Distinction Institute, is an internationally known authority in helping companies create amazing customer experiences.
