@article{articleea908edd,
title   = {'Er POT.3+' -doped germanate glasses for active waveguides prepared by 'Ag POT.+'/'K POT.+'<--> 'Na POT.+' ion-exchange},
author = {Barbosa, A. J. and Maia, L. J. Q. and Nascimento, A. M. and Gonçalves, Rogéria Rocha and Poirier, G. and Messaddeq, Y. and Ribeiro, S. J. L.},
year = {2008},
journal   = {Journal of Non-Crystalline Solids}
}