@article {,
	title = {Membrane division, Restricted Membrane Creation and Object Complexity in  P Systems},
	journal = {International Journal of Computer Mathematics},
	volume = {83},
	year = {2006},
	pages = {529-547},
	address = {Londres},
	author = {Artiom Alhazov and Rudolf Freund and Agust{\'\i}n Riscos-N{\'u}{\~n}ez}
}
