<https://www.coursera.org/learn/dianci-2#mooc>
<http://schema.org/Name>
"电磁学下——恒磁场与时变电磁场"
<https://www.coursera.org/lecture/dianci-2/6-14jiang-zuo-zhi-si-cong-wu-li-li-xian-dao-dian-ci-chang-li-lun-HVcJS>