When submitting an article to some Elsevier journals, under Enter Comments it is stated "It is mandatory to provide the names and contact details (e.g. e-mail addresses) of 3 potential referees here and any comments you would like to send to the editor. These comments do not appear in your manuscript.". There is also a distinct item Suggest Reviewers. What is the difference between referees and reviewers, what is the role of referees, and how to select them?
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