@article{EJDE_2009__2009__a22,
     author = {Shibata,  Tetsutaro},
     title = {Precise asymptotic behavior of solutions to damped simple pendulum equations},
     journal = {Electronic journal of differential equations},
     year = {2009},
     volume = {2009},
     zbl = {1186.34026},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/EJDE_2009__2009__a22/}
}