Xiaojing Yang. Multiple periodic solutions for a class of second order differential equations. Appl. Math. Lett., 18(1):91-99, 2005. [doi]
@article{Yang05:29,
title = {Multiple periodic solutions for a class of second order differential equations},
author = {Xiaojing Yang},
year = {2005},
doi = {10.1016/j.aml.2004.06.020},
url = {http://dx.doi.org/10.1016/j.aml.2004.06.020},
researchr = {https://researchr.org/publication/Yang05%3A29},
cites = {0},
citedby = {0},
journal = {Appl. Math. Lett.},
volume = {18},
number = {1},
pages = {91-99},
}