Am Mo., 28. Jan. 2019 um 16:40 Uhr schrieb Baris Erkus <
bariser...@hotmail.com>:
> I observed that if biblatex is selected for the bibliography style, the
> \usepackage[*options*]{biblatex} is placed right before the
> \begin{document}, but not after the \documentclass, where usually packages
> are called.
>
Yes, because biblatex must be loaded after babel (or polyglossia), and
this, in turn, must be loaded late.
> If I want to place some code in the preamble that requires the biblatex
> package, then these codes appear before the
> \usepackage[*options*]{biblatex} line, and they do not work.
>
> For example I wanted to replace "et al.", "and", "Bibliography (title)"
> with their Turkish counterparts by simply placing the following code to the
> preamble:
>
> \DefineBibliographyStrings{english}{%
> references = {{Kaynaklar}},
> and = {ve},
> andothers ={ve diğerleri},
> }
>
> but it does not work.
>
You need to embrace such definitions in \AtBeginDocument{...}. See
https://wiki.lyx.org/BibTeX/Biblatex#toc2
HTH,
Jürgen
