The phrase "an example of sustained" is correct and usable in written English.
It can be used when referring to a specific instance or case that demonstrates a continuous or prolonged action, quality, or effect.
Example: "The study provided an example of sustained effort in improving community health over several years."
Alternatives: "a case of ongoing" or "an instance of prolonged".
An example of sustaining momentum is the recent protest that shut down the Dan Ryan Expressway in Chicago.
The sequence is a masterly example of sustained gag-building, and proof that, even for the most inoffensive and presentable man, everything can go disastrously wrong.
In 2016 and 2017, the "Candlelight Protests" in South Korea against then-President Park Geun-Hye are an example of how sustained, organized protests can convey a sense of urgency to governmental officials.
An example of a sustained changing cell that signals learning with decreased firing rate is not available in Wirth et al. (2003).
A wrestler's hammerlock, because its effects come and go with the presence or absence of the cause itself, is an example of a sustaining cause.
At the end of the trial, the judge, Mr Justice Mackay, said that, in his 30 years in the legal profession, he regarded Balfour Beatty's failure as the "worst example of sustained industrial negligence in a high-risk industry he had ever seen".
Mel Gibson's movie about the torture and agony of the final hours of Jesus is the bloodiest, most brutal example of sustained sadism ever presented on the screen.
All you need is the 11 studio albums, from Please Please Me to Let It Be, which form the greatest example of sustained brilliance in pop.
Dysregulation of the NF-κB system observed in the present study is associated with chronic alcoholism, and as such represents the first example of sustained transcriptional adaptation to chronic intake of substances of abuse in the human brain.
One important example of sustained chronic inflammation and failure of its resolution is found in atherosclerosis.
