Fil:Greatwall large.jpghttps://creativecommons.org/publicdomain/mark/1.0/PDMCreative Commons Public Domain Mark 1.0falsefalse The original description page was here. All following
Fil:Working With Historical Data.jpgaccessibility for the general public. Date 13 May 2019 Source File:Greatwall_large.jpg Author Henrike Rudolph adapted from Herbert Ponting [Public domain]