Revtex sometimes includes DOI in references

It looks like revtex includes DOIs rather than using the URL at random for references. It turns out this is if no page is defined (see https://tex.stackexchange.com/questions/298033/revtex-adds-doi-numbers-seemingly-at-random-after-citations).

We should check if using `pages={-}` works generally or if it will break (or produce pages as '-') for other bib styles.