@inproceedings{joão1975an,
title={An extension of Nachbin’s theorem to differentiable functions on Banach spaces with the approximation property},
author={João B. Prolla, and Claudia S. Guerreiro},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203459208350254},
booktitle={Arkiv for Matematik},
volume={14},
number={1},
pages={251-258},
year={1975},
}
João B. Prolla, and Claudia S. Guerreiro. An extension of Nachbin’s theorem to differentiable functions on Banach spaces with the approximation property. 1975. Vol. 14. In Arkiv for Matematik. pp.251-258. http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203459208350254.