> Maybe the mla style is not installed on your system, you can get it > from CTAN mirrors. Just try a few other "Styles" from the drop-down > list (click on BibTeX Generated Bibliography to see it), most of them > create sorted output. You could try apalike.
A I stated before I did not use BiBTeX for adding the Bib items. I just used the LyX environment Bibliography. Idon't have any BibTex generated items (unfortunately) and I can't find any configuration dialog to input the style. Is it possible to write it explicitly in LaTeX?