I share a link about including multiple bibliographies in one document.
Babel and the bibliography
I show how it’s possible to use foreign languages in the bibliography.
Bibtex: diacritics in author’s names
I show how to add diacritics in authors’ names in the bibliography.
Bibtex: multiple source files/databases
I show how multiple bibliography files can be included in one document without causing problems (with natbib).
Bibtex: forcing capital letters
BibTeX likes to make non-initial capital letters lower case. I show how to defeat BibTeX’s stubbornness.