Authority referred to "Wang, 1983" without explanation. [details]
Pingquan, Hebei, China [details]
Pingquan, Hebei, China [details]
Luanping, Hebei, China [details]
Mentougou district, Beijing, China [details]
Pingquan, Hebei, China [details]
Pingquan, Hebei, China [details]
Pingquan, Hebei, China [details]
Pingquan, Hebei, China [details]
Pingquan, Hebei, China [details]
Mentougou district, Beijing, China [details]