Table 3.

PubMed indexed papers on the subject paper mills in scientific publishing

Author, year	Type	Content
Hvistendahl, 2013	News	An early disconcerting report on the scientific publication industry in China, including a description of practices (“…the company buys data from a national laboratory in Hunan province.”) that maybe describes how the paper mill industry produce manuscripts
Byrne et al., 2019	Review	Building on their 2017 published discovery on a large cluster of similar papers, the authors state that understudied human-genes form an easy target for the paper mill industry. This generates large amounts of false data that may pose serious delays in genuine biomarker research. The authors sensibly hypothesize on the modus operandi of paper mills, which also provides options for preventing publication of paper mill products
Byrne and Christopher, 2020	Review	A comprehensive review on paper mills, their history, business model, and presumed operational methods. It introduces the terms “invented images” and “stock images,” and provides methods for screening paper mill products by editors, journal staff, and peer reviewers. Includes several citations to interesting non-PubMed indexed papers on publication pressure
Moore, 2020	Editorial	Argues that unfindable scientific content of predatory journal papers and preprint servers feed the paper mill industry. Plagiarism detection software is fooled and image manipulation detection by the human eye still forms the cornerstone in uncovering paper mill products
Hackett and Kelly, 2020	Editorial	States that journals, like BiO are victim of the paper mill industry, and defines their strategy (Publishing Ethics Coordinator, in house detection by image spotters, software development, raw data requests upon identification of image issues) to defend against paper mill products
Teixeira da Silva, 2021	Letter	Argues that besides paper mills and their customers, also reviewers (publons), editors (citations), journals (impact factor), and indexing agencies and search machines benefit from paper mill activities. Upon discovery of a paper mill (paper), all in the publication ecosystem that profit should suffer consequences
Mallapaty, 2020	News	Reports on new rules from the Chinese science ministry on dealing with research misconduct. These new rules also target those active in the paper mill industry
Frederickson and Herzog, 2021	Editorial	Indicates that paper mills have affected the Molecular Therapy journal family, and states new submission requirements to fight against paper mill products entering their journals
Seifert, 2021	Editorial	Indicates that Naunyn–Schmiedeberg’s Archives of Pharmacology became a victim of paper mills. Lists 20 features of paper mill products, and provides strategies (institutional email address requirement, supplemental original source data, supplemental immunoblot data, explicit author statement that no paper mill was involved) to prevent paper mill submissions
Heck et al., 2021	Editorial	Summarizes the hallmarks of paper mill products. Reports that 5–10% of total amount of recent submission to the International Journal of Cancer bear such suspicious marks. Warns the paper mill industry and their costumers not to submit their papers to this journal since their money will be lost
Else and Van Noorden, 2021	Comment	Reports on the act of transparency by the Royal Society of Chemistry on a large series of retractions of paper mill products from their journals. Describes the paper mill industry characteristics and the work of research integrity analysts, also known as “research integrity sleuths.”