@article{articlee4e41389,
title   = {Stability and surface acidity of niobium (v) oxide grafted on a silica gel surface},
author = {Denofre, S and Gushikem, Y and Castro, S C and Kawano, Yoshio},
year = {1993},
doi = {10.1039/ft9938901057},
journal   = {Journal of Chemical Society}
}