I recently sent the following letter to a journal of questionable reputation:
To whom it may concern:
In the [Journal Redacted], in the paper titled [Paper Redacted] by [Authors Redacted], the following section is plagiarized from Wikipedia:
That section is copied from this Wikipedia article: [Link Redacted]
They replied with the following:
Dear Mr. [Name Redacted], As you mention that there is plagiarism. Yes, I read the research again but that part is from introduction. Introduction part is not part of the research. Please read it again...
I replied with:
Sir or Madam,
You are correct that is from the introduction, but any usage of non-original material whether part of the research or not must be properly cited or it is plagiarism. Even if this were an opinion piece and not research, this would be plagiarism. I expect this will be addressed soon.
They replied with:
Dear sir, I will inform to author for proper reference citation of the paper.
What do I do at this point? If they take corrective action, it will take some time. How much time is it appropriate to give them before I report them elsewhere?