%0 Journal Article %A McLaughlin, D. %A Poliquin, R. %A Vanderwerff, J. %A Zizler, V. %T Second-Order Gâteaux Differentiable Bump Functions and Approximations in Banach Spaces %J Canadian journal of mathematics %D 1993 %P 612-625 %V 45 %N 3 %U http://geodesic.mathdoc.fr/articles/10.4153/CJM-1993-032-9/ %R 10.4153/CJM-1993-032-9 %F 10_4153_CJM_1993_032_9