While desktop search engines like Beagle and Recoll can quickly find any file on your hard disk, they can't help you organize documents and files into neat and easy-to-manage collections. That's why we have tools like digiKam for managing your photos, BasKet Note Pads for keeping tabs on your notes, and Referencer for filing and tagging your documents. The latter is not only a handy tool to herd your documents, it also makes an excellent research and bibliography tool.
In addition to source code, Referencer packages are available for several Linux distros, including Debian, Mandriva, and ZenWalk. If you are using Ubuntu, or any of its derivatives, you can grab a .deb package for it from GetDeb.
Referencer's interface is simplicity itself. The main Library window is used to manage documents in the current library, while the left Tag pane contains tagging tools. Since Referencer doesn't actually store documents but rather links to them, it can handle virtually any file type: PDF, Writer documents, graphics files, Web pages, etc. Adding documents to the current library is a no-brainer: just drag the document you want to add onto the library window. Alternatively, you can use the Documents -> Add Folder to add multiple documents from a directory. You can open any document in the library by double-clicking on it.
Once you've added a document to the library, you should specify its metadata, which Referencer uses to generate a BibTeX bibliography and add citations to a LyX document. To add metadata, right-click on the document and select Properties from the context menu. In the Properties dialog window you can specify document metadata by filling out the relevant fields. If you have bibliographical data for the current document in the BibTeX format, you can copy it in the clipboard and paste it into the appropriate fields in the Properties window by pressing on the Paste BibTeX button.
Adding metadata by hand can be laborious. Fortunately, Referencer sports a clever feature that automates the process. The application supports automatic metadata retrieval from online resources such as arXiv, PubMed, and CrossRef, as long as the PDF document you're adding to the library contains either the arXiv ID or DOI code. When Referencer detects the code it automatically retrieves the metadata and populates the appropriate fields in the document's properties. Besides adding documents stored on your hard disk, you can add references that contain bibliographical metadata but don't link to any file or document. Using the Documents -> Add Reference with ID command, for example, you can create a library entry with metadata based on an arXiv ID or DOI code. Using the Add Empty Reference command allows you to create an empty entry and enter metadata manually. The Referencer's import feature gives you the ability to import BibTeX, Reference Manager, and EndNote files -- handy if you want to turn existing bibliographies into Referencer's libraries. To import a bibliography file, choose Library -> Import and select the file you want to add.
Tagging is another important aspect of organizing documents in your library. First, you have to create tags, which you can do by choosing Tags -> Create Tag or using the Ctrl-T keyboard shortcut. Next, select a document in the library and tick the tags you want to assign to the document. The list of all tags appears at the top of the Tag pane as a tag cloud (an alphabetical list of tags, where the importance of a tag is shown with the font size). Using tags, you can easily locate documents in your library by selecting the tag you want. There are also two sections in the Tag pane that allow you to view all documents in the library or untagged documents.
The Search field provides another way to quickly find the documents you are looking for. This feature searches documents using the Key value. To find a document, start by entering the desired key value, and Referencer automatically narrows the search results as you're typing.
When it comes to using Referencer as a bibliographic tool, you have two options. If you're using LyX as your document processor, you'll be pleased to learn that Referencer can insert citations directly in LyX via the dedicated Cite in LyX command or button. You can also export your library as a BibTeX bibliography file for use with other applications.
Despite its simplicity, Referencer is a useful application that can help you to kill two birds with one stone. You can use the application to organize your documents into easy-to-manage searchable libraries. And the ability to retrieve and manage metadata combined with the ability to handle bibliography files makes Referencer a great tool for researchers and writers alike.