%0 Conference Proceedings %T EFFECT of BaO and LiO2 ADDITION on the SINTERING BEHAVIOUR of APATITE.MULLITE GLASS. CERAMICS SYSTEM %A Roza Sehhat %A Mollazadeh Beidokhti, Sahar %A Bijan Eftekhari Yekta %A Jafar Javadpour %J Advances in Applied Physics and Materials Science %D 2011