Some other Chinese arts , not in the Wudangquan group , such as Qigong , Liuhebafa , Bak Mei Pai , Zi Ran Men ( Nature Boxing ) , Bok Foo Pai and Yiquan are frequently classified ( or classify themselves ) as `` internal '' .
Some other Chinese arts , not in the Wudangquan group , such as Liuhebafa , Bak Mei Pai , Bok Foo Pai and Yiquan are frequently classified ( or classify themselves ) as `` internal '' .