1. Correction: Long-Distance Connections in the Copper Age: New Evidence from the Alpine Iceman's Copper Axe;Artioli, G., Angelini, I., Kaufmann, G., Canovaro, C., Dal Sasso, G., and Villa, I. M.,2017
2. A Weapon Like no Other: The Ancient Chinese Sword of Goujian, Found in a Tomb, is Perfectly Sharp After More Than 2,500 Years;Andrews,2017
3. 7 Oldest Coins that Ever Existed,2008
4. The Top 20 Economies in the World,2019
5. How Many Aluminum Cans Equal 1 Pound?;Australian Aluminum Council,2014