Changhsingium: Verskil tussen weergawes

* {{en}} Jin, Y.; Wang, Y.; Henderson, C.; Wardlaw, B.R.; Shen, S. & Cao, C.; 2006: ''The Global Boundary Stratotype Section and Point (GSSP) for the base of Changhsingian Stage (Upper Permian)'' Episodes '''29(3)''', p. 175-182.