Array ( [0] => Array ( [title] => L20A [link] => https://www.youtube.com/embed/fHtU72QqN5k ) [1] => Array ( [title] => L20B [link] => https://www.youtube.com/embed/Y-TU1wQflhU ) [2] => Array ( [title] => L20C [link] => https://www.youtube.com/embed/KfxQ8kOZUs8 ) ) 國立清華大學開放式課程OpenCourseWare(NTHU, OCW) - Lecture 20 | Equivariant normal form theorem; Procedure of local bifurcation analysis