refdbd implements 4 standard backends for data output. You can select them with the -t option of the getref command in refdbc. Remember that all backends just send data. It is your decision what you want to do with the information. You can either view the data on the screen or pipe them to another application or write them to a disk file.
The screen backend provides a basic data output for viewing in a terminal, preferably through a pager. By default, the reference ID, the publication year, the authors, the title, and the source information are displayed. You can use the -s option to additionally display the abstract (AB or N2), the notes (N1), the reprint info (RP), the address (AD), the publisher (PB), the city (CY), the URL (UR), and the user (U1 through U5) and misc (M1 through M3) fields.
The html backend works just like the scrn backend, but encodes this information in a HTML text. This comes in handy if you would like to view the results of your queries in a web browser. You simply use the -o switch to write the results of your queries to a file, reusing the same filename for each query. After each query you just have to hit the reload button of your browser to view the results of the current query.
The visual appearance of the generated HTML files can be customized using CSS files. The URL of the CSS file must be specified with the refdbc -G command-line option or by setting the configuration variable cgiurl. The following element classes can be customized. In most cases, the class name reflects the database field to be formatted:
H1.h1
H2.id
P.title
P.authors
P.abstract
P.note
P.address
P.city
P.publisher
P.m1, P.m2, P.m3
P.u1, P.u2, P.u3, P.u4, P.u5
P.url
EM.periodical
EM.volume
EM.issue
EM.page
This backend provides output formatted for use as a bibtex reference database. This can be used with the tex and bibtex applications to create bibliographies for documents written with Donald Knuth's famous TeX typesetting system. The -s option cannot be used with this backend and will be ignored.
The DocBook backend formats the query result as a bibliography element in a SGML document using the DocBook DTD (the same output can be used as an XML document). The -s option cannot be used with this backend and will be ignored. This option is called "db31" to distinguish it from any later additions that may be necessary due to possible incompatibilities in new DocBook versions. It just means that the SGML that this backend creates should work with DocBook V.3.1 or later unless a new backend will be added.