For scholars who quote other scholars over and over again (and forget more and more what the quoted text actually is saying), citation managers are a must. Endnote is one of the main contenders here, expensive but generously sponsored by universities. The same can be had for free and compatible with plain text. CiteProc is integrated in pandoc, the swiss army knife of plain text conversion. Point to a bibtex file - e.g. automatically exported from Zotero - and when you use a special notation, e.g. [@bibtexkey], in text the result is formatted automatically upon conversion including the bibliography at the end of the text. For more details see the man page of pandoc-citeproc. All kinds of citation styles are available. As a bonus, the Atom editor has a plugin which lets you choose the reference interactively when hitting Alt-Z.