After some gray hairs with TikZ, all boils down to this simple example
A list within a list. The behaviour can be resolved, though:
Why does it work? David Carlisle tells us in our chat room:
because it you add and then the files (a useful emacs feature) you find it starts to go wrong at , i.e. the bibliography is being set at the point LaTeX has just seen but hasn't yet set that item. So things are held back to (e.g.) add a bullet point at the start of the next paragraph. The just gets that out of the way so the references start in the second paragraph of the center environment, not the first.
I am not quite sure about the benefits of this center-environment that is introduced by the class, i have dropped the teamm a note. Hopefully, an update is on CTAN soon.
In the meantime, i made a fork and removed the center environment. Bitbucket Tikzposter Fork
answered May 8 '15 at 13:39
If you want your bibliography sorted exactly as in your bibliography file independently of the order you cite them or any other predefined order, then I think you shouldn't bring BibTeX to the table. In that case you should build the bibliography manually using the environment and commands.
Using BibTeX, the bibliography file works as a database. Only those references included with commands and will be in the reference list of your document, i.e. including more references in the bibliography file will not automatically add them to the bibliography of your document.
The order of your references inside the bibliography file doesn't really matter. The order they will come up depends on the bibliography style you choose (see slhck's comment to your question). Keep in mind that after switching styles it might be necessary to delete you .aux file in order for the changes to apply. Then compile the file until no "references might have changed" warnings appear then use bibtex and finally another run of latex/pdflatex should do it.
Point 8 in this page describes a way of overriding the default order of the style you choose.
answered Nov 23 '13 at 23:01