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I was asked to review a technical paper for a journal at a large commercial publisher. The paper extends on another publication that is cited several times throughout the document. The cited paper was published at the same publisher but in a different journal. I work for an R&D department in a private company. We do not have a subscription with the publisher and no budget to buy articles (at least not in cases like this). I.e., I cannot access the cited paper. Would it be acceptable to ask the editor of the journal I review for to provide me with the cited paper?
Additional Information: The review process is double blind, so I do not know if the cited paper and the paper I'm reviewing are from the same authors. Given the specific topic, it seems likely to me. This is why I did not ask the authors for a copy. I was also unable to find a free version of the paper online.
Outcome: I asked the editor for the paper and received a copy within hours. Along with ads for a subscription of that journal.