@article {1134,
	title = {Comparative analysis of hybrid-Trefftz stress and displacement elements},
	journal = {Archives of Computational Methods in Engineering. State of the art reviews},
	volume = {6},
	year = {1999},
	pages = {35-39},
	author = {Freitas, J. A. T. and C. Cismasiu and Z. M. Wang}
}
