@inproceedings{j.1956on,
title={On the differential equations of Hill in the theory of the motion of the Moon (II)},
author={J. F. Steffensen},
url={http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203144043229827},
booktitle={Acta Mathematica},
volume={95},
number={1},
pages={25-37},
year={1956},
}
J. F. Steffensen. On the differential equations of Hill in the theory of the motion of the Moon (II). 1956. Vol. 95. In Acta Mathematica. pp.25-37. http://archive.ymsc.tsinghua.edu.cn/pacm_paperurl/20170108203144043229827.