I shall request you with all humility to co-operate with this mission and thus be benefited yourself. It is not the least exaggeration but actual fact and to become a member for this mission will to your own interest: Revision history
Diff selection: Mark the radio buttons of the revisions to compare and hit enter or the button at the bottom.
Legend: (cur) = difference with latest revision, (prev) = difference with preceding revision, m = minor edit.