Bibliography behaves strange in lyx

I have created a Bibliography section in my document written in lyx. It uses a book layout.

For some reason it did start over again when I added some more entries. The new entries was made some time later than the first ones. I just went down to key-27 and hit enter. Then it started on key-1 again.

Does anyone know why it behaves like this?

EDIT: If I save the document and exit. The next time I open it, LYX starts the numbering at key-1 again even if it already exist. If I manually change one key to an existing one, I get a message saying it already exist.

The lyx code is below.

\begin{thebibliography}{34}
\bibitem{key-6}Lego mindstorms, http://mindstorms.lego.com/en-us/default.aspx

\bibitem{key-7}C.A.R. Hoare. Communicating sequential proce开发者_如何学运维sses. Communications of the ACM, 21(8):666-677, pages 666\textendash{}677,
August 1978.

\bibitem{key-8}C.A.R. Hoare. Communicating sequential processes. Prentice-Hall, 1985.

\bibitem{key-9}CSPBuilder, http://code.google.com/p/cspbuilder/

\bibitem{key-10}Rune Møllegård Friborg and Brian Vinter. CSPBuilder - CSP baset Scientific Workflow Modelling, 2008.

\bibitem{key-11}Labview, http://www.ni.com/labview

\bibitem{key-12}Robolab, http://www.lego.com/eng/education/mindstorms/home.asp?pagename=robolab

\bibitem{key-13}http://code.google.com/p/pycsp/

\bibitem{key-14}Paparazzi, http://paparazzi.enac.fr

\bibitem{key-15}Debian, http://www.debian.org

\bibitem{key-16}Ubuntu, http://www.ubuntu.com

\bibitem{key-17}GNU, http://www.gnu.org

\bibitem{key-18}IVY, http://www2.tls.cena.fr/products/ivy/

\bibitem{key-19}Tkinter, http://wiki.python.org/moin/TkInter

\bibitem{key-20}pyGKT, http://www.pygtk.org/

\bibitem{key-21}pyQT4, http://wiki.python.org/moin/PyQt4

\bibitem{key-22}wxWidgets, http://www.wxwidgets.org/

\bibitem{key-23}wxPython GUI toolkit, http://www.wxPython.org

\bibitem{key-24}Python programming language, http://www.python.org

\bibitem{key-25}wxGlade, http://wxglade.sourceforge.net/

\bibitem{key-26}http://numpy.scipy.org/

\bibitem{key-27}http://www.w3.org/XML/

\bibitem{key-1}IVY software bus, http://www2.tls.cena.fr/products/ivy/

\bibitem{key-2}sdas

\bibitem{key-3}sad

\bibitem{key-4}sad

\bibitem{key-5}fsa

\bibitem{key-6}sad

\bibitem{key-7}

\end{thebibliography}

You should look into using BibTex (for example Zotero can export to a BibTex format). That way you don't need to code in LaTex, and can just do Insert > Citation to add citations to your document and add a bibliography at the end which will be be automatically generated and updated.