Ricardo Azambuja Silveira Eduardo Rodrigues Gomes Rosa Vicari Improving Interoperability Among Learning Objects Using FIPA Agent Communication Framework. 51-60 2006 conf/clor/2006 IFIP PPAI http://dx.doi.org/10.1007/978-0-387-34749-3_6 db/conf/ifip12/ppai2006.html#SilveiraGV06