Aigaion Reference Management System - Aigaion is a bibliography management system that seems to be the perfect tool for managing your bibliography and references.

Papers by ReadCube - ReadCube Papers is a sumptuous reference manager helping out academic writers to get the most out when it comes to access and discovering more citations with multiple libraries or databases.

Pybliographer - Pybliographer is a tool that helps you manage your bibliographic databases in a user-friendly way.

I Librarian - I Librarian is an online tool that comes with a great way to handle and manage your PDF paper and office documents.

BibBase - BibBase.org is an easy way to set up and maintain a scientific publications page.

Qiqqa - Qiqqa is a free research and reference management software. It can be used in many organizational projects from the academic to the personal to the business endeavor. Read more about Qiqqa.