The phrase "a source of enduring" is correct and usable in written English.
It can be used to describe something that provides lasting or long-term value, influence, or support.
Example: "The novel became a source of enduring inspiration for generations of readers."
Alternatives: "a wellspring of lasting" or "a reservoir of perpetual".
About all those benighted and deluded Lib Dem MPs who always thought that SD was one of their greatest strengths – instead, now, of a source of enduring shame.
To those affected by the blast on Mount Gearheart the Japanese campaign is not a historical footnote, or a terror template, but a source of enduring grief.
But crowd estimates for Washington demonstrations are a source of enduring controversy, particularly since the park police stopped making its own estimates.
That was widely seen as an indirect rebuff to the United States, which offered similar help to Pakistan's rival, India, in 2006 — a source of enduring resentment in Pakistan.
The attack remains a source of enduring mystery here, just a few miles from Chechnya, the adjacent region where war and lawlessness have simmered for most of the last decade.
Their stand against injustice and the positive action they took to try and overcome it ought to be a source of enduring pride and inspiration to all of us in Britain.
The concessions in essence created two separate classes of autoworkers via a two-tier wage system -- a term now underlined by many workers as the source of enduring unhappiness.
Yet his Islam is also the source of enduring monuments of thought and piety and art.
Shifts in commodity prices and currencies tend to be one-off effects, not the source of enduring inflationary pressure.
The targeting of Mr Baransu and his newspaper, Taraf, is yet another example of Mr Erdogan's campaign to muzzle dissident voices.A source of enduring speculation is why Mr Erdogan has chosen this moment to go after the Gulenists.
Dunham suggests as much in "Tiny Furniture" and makes it explicit in "Girls": desire isn't inherently progressive, rational, orderly, or constructive; it often entails ugly emotions, self-abasement, and even potential danger; and it's the one vital source of enduring romance.
