You can link to your preferred Bibliography/Citation tool in Srivener via Options -> General -> Bibliography/Citations Manager. Once you have set it up you can open your citation tool with Format -> Bibliography/Citations...

This option is an advantage for me because I can keep all the Bib/Cit stuff in Zetero standalone. http://www.zotero.org/support/3.0#zotero_standalone

You can copy/paste citations or bibliographics from Zotero to Srivener or export the bibliographics list as an rtf file an import it in Scrivener.

Dominik