# Modify bibliography categories

I'm currently writing my masterthesis (in german) and am using biber in combination with jabref for my citations. I have some citations related to "Masterarbeiten" and "Diplomarbeiten", for which I chose the category "masterthesis". Now, when the bibliography is created in german language, instead of "Masterarbeit" "Magisterarbeit" is shown in the document. This is not correct and so I would like to change this. What do I have to do to change this, so that "Masterarbeit" will be written instead of "Magisterarbeit"? And secondly: What do I have to do if I want to create a second category, so that I can distinguish between the citation of a "Diplomarbeit" and a "Masterarbeit"?

I appreciate any help!

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Just to be sure: You're using biblatex, don't you? –  lockstep Oct 23 '11 at 22:12

Use the @thesis category and add a type field to specify the type. With \NewBibliographyString you can create the type gethesis (ge: graduate engineer), with \DefineBibliographyStrings you can add/change string definitions for the ngerman language.

\documentclass{article}

\usepackage[ngerman]{babel}

\usepackage[abbreviate=false]{biblatex}

\NewBibliographyString{gethesis}
\DefineBibliographyStrings{ngerman}{%
mathesis = {Masterarbeit},
gethesis = {Diplomarbeit},
}

\usepackage{filecontents}

\begin{filecontents}{\jobname.bib}
@thesis{A01,
author = {Author, A.},
year = {2001},
title = {Alpha},
type = {mathesis},
}
@thesis{B02,
author = {Buthor, B.},
year = {2002},
title = {Bravo},
type = {gethesis},
}
\end{filecontents}