Sun, Z.; Xie, K.; Li, Z.A.; Sinev, I.; Ebbinghaus, P.; Erbe, A.; Farle, M.; Schuhmann, W.; Muhler, M. Ventosa E. "Hollow and yolk-shell iron oxide nanostructures on few-layer graphene in li-ion batteries" Chemistry - A European Journal 20, pp. 2022 - 2030. 2014