I find it best to link to the NASA ADS record, so that people can go to the published record if they can, or the arxiv record if they can't. Also makes it easier to chase down references.

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"What do you care what other people think?" -- Richard Feynman
"For a successful technology, reality must take precedence over public relations, for nature cannot be fooled." -- Feynman, at the conclusion of his Challenger report