Article 198 Valeri S.Harutyunyan Vahram P.Mkrtchyan Minas K.Balyan Ashot P.Aivazyan Eduard S. Abovyan Paulo J.M.Monteiro Journal of the American Ceramic Society 86, 12 2162-2166 2003 http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1551-2916