What is more interesting, these 14 articles over citing Khamdamov's publications were also coauthored by Khamdamov himself, implying that he got the high number of citations through a practice of high self-citations. At this stage, will the publishers step in for a further investigation?

After an investigation (please find the details of the method at: www.5gh.org.cn/WuGH/2025/00...), we find 14 articles over citing Khamdamov's publications. Over 30% of each article's references were coauthored by Khamdamov.

We came across the Googe Scholar profile of Shoh-jakhon Khamdamov at Tashkent State University of Economics, and noted the abnormal pattern of the citations to Khamdamov. The profile shows that Khamdamov got 382 citations in the year of 2024, the number is 5 times higher than that in the 2023.

Do you mean some organizers allow authors to republish previous article without the permit from the publisher(s)/conference organizer(s)?

There is a reply (www.5gh.org.cn/WuGH/2025/00...) from the authors. The 5GH Team appreciates the clarification by Dr. Payne.

I have two questions: (1) What criteria should I look for to determine whether a publisher/journal is predatory? (2) What actions can be taken if it is a predatory publisher?

You can also find the extracted data in the Excel file at: www.5gh.org.cn/WuGH/2025/00...

(2/2) The data extracted is shown in lower-left panel, the reproduced Tauc plot is shown in the lower-right panel, while the original Tauc plot is shown in the upper-right panel.