Last year, a researcher at a U.S. university received an email offering what the subject line described as a "great opportunity to publish an article." The author of the email, Mahdi Shariati, an adjunct professor of civil engineering at Ton Duc Thang University, in Vietnam, said he had read one of the researcher’s papers and was impressed by its quality.

With more than 12,000 citations to name of Mahdi Shariati, according to Clarivate’s Web of Science, his ranks among the most highly cited researchers in his field. He is a frequent referee for journals from major publishers and this year has been a guest editor for both Sage and MDPI.

But the researcher who received the offer to collaborate felt Shariati’s profile was "very suspicious." Researchers emailed Shariati to ask how he was able to guarantee publication and citations even before seeing the manuscripts he suggested coauthoring. Researchers have not heard back.