There's a study on it here: https://pmc.ncbi.nlm.nih.gov/articles/PMC10691350/
And here: https://www.sciencedirect.com/science/article/pii/S266651822100022X
An article about a specific retraction of a study on mentorship: https://www.psychologytoday.com/gb/blog/checkpoints/202101/the-bad-retraction
The lancet removed (although not formally retracted) an article on covid-19 in Gaza https://blogs.bmj.com/bmj/2021/06/02/political-censorship-in-academic-journals-sets-a-dangerous-new-precedent/
China has allegedly forced at least one person to retract a study about public opinion on it https://retractionwatch.com/2024/07/10/author-blames-retraction-on-chinese-censorship/
It sure is nice of the US government to compile a list of sources for us https://ustr.gov/sites/default/files/2024%20Review%20of%20Notorious%20Markets%20of%20Counterfeiting%20and%20Piracy%20(final).pdf