@inproceedings{bengt1964properties,
title={Properties and asymptotic behaviour of the solutions of coupled diffusion equations with time-periodic, space-independent coefficients, with an application to electrodiffusion},
author={Bengt Nagel},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203432343920027},
booktitle={Arkiv for Matematik},
volume={5},
number={3},
pages={363-390},
year={1964},
}

Bengt Nagel. Properties and asymptotic behaviour of the solutions of coupled diffusion equations with time-periodic, space-independent coefficients, with an application to electrodiffusion. 1964. Vol. 5. In Arkiv for Matematik. pp.363-390. http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203432343920027.