Array ( [0] => Array ( [title] => L7A [link] => https://www.youtube.com/embed/2agW-yMfo6Y ) [1] => Array ( [title] => L7B [link] => https://www.youtube.com/embed/ZjuPTsf-ig8 ) [2] => Array ( [title] => L7C [link] => https://www.youtube.com/embed/dLduCs-PSs4 ) ) 國立清華大學開放式課程OpenCourseWare(NTHU, OCW) - 第7講 point group (orthorhombic + tetragonal + trigonal + hexagonal)