Zotero is my favorite application for organizing, sharing, and generating bibliographies for research papers. There are many other similar reference managers such as Mendeley and EndNote with superior features. They are either not open source or free (as in beer) or both. .

Zotoro gets the job done for me. It has got a lot of useful features. One such function is that a citation can be exported to clipboard so that it can be pasted into a document. This can be achieved using ⌘ + ⇧ + c keyboard shortcut.

You can export the citation in a variety of formats. However, if you are using LaTeX to write a paper, you almost always need to paste a quote in a BibTex format into a bib file. There are a few ways of achieving this as mentioned in the forum thread. I found that the easiest way is to download and install the BibTex generic citation style from the Zotero style repository. After installing, set the default export format to BibTex generic citation style as shown below.