Earlier today I quoted an article published by Mechon Mamre with no written author. The article is: https://mechon-mamre.org/jewfaq/animals.htm
The quote I used from them as a source was "Under Jewish law, animals have some of the same rights as humans do. Animals rest on Shabbat, as humans do. We are forbidden to muzzle an ox while it is working in the field, just as we must allow human workers to eat from the produce they are harvesting."
It's established that quoting Scripture from Mechon Mamre is a source, but is an unnamed writer from the website a valid Jewish source?