@article{JIPAM_2006__7_3_116853,
     author = {Jiang, Wei Dong and Yun, Hua},
     title = {Sharpening of {Jordan's} inequality and its applications.},
     journal = {JIPAM. Journal of Inequalities in Pure & Applied Mathematics [electronic only]},
     publisher = {mathdoc},
     volume = {7},
     number = {3},
     year = {2006},
     zbl = {1182.26056},
     language = {en},
     url = {https://geodesic-test.mathdoc.fr/item/JIPAM_2006__7_3_116853/}
}