@article {,
	title = {Computational Completeness of P Systems with Active Membranes and Two Polarizations},
	journal = {Lecture Notes in Computer Science},
	volume = {3354},
	year = {2005},
	pages = {82-92},
	publisher = {Springer},
	address = {Amsterdam, The Netherlands},
	abstract = {P systems with active membranes using only two electrical charges and only rules of type  i.e., evolution rules used in parallel in the regions of the membrane system, and of type  i.e., communication rules sending out an object of a membrane thereby possibly changing the polarization of this membrane, assigned to at most two membranes are shown to be computationally complete, which improves the previous result of this type with respect to the number of polarizations as well as to the number of membranes. Allowing a special variant  of rules of type  to delete symbols by sending them out, even only one membrane is enough.
},
	isbn = {978-3-540-25261-0},
	issn = {0302-9743},
	doi = {10.1007/b106980},
	url = {http://www.springerlink.com/index/7mllx684jbabqtk2.pdf},
	author = {Artiom Alhazov and Rudolf Freund and Gheorghe Paun}
}
