Citation Hunt

The Wikipedia snippet below is not backed by a reliable source. Can you find one?

Click I got this! to go to Wikipedia and fix the snippet, or Next! to see another one. Good luck!

In page Khyber Pakhtunkhwa:

"

During the times of Indus Valley Civilisation (3300 BCE – 1700 BCE) the Khyber Pass through Hindu Kush provided a route to other neighbouring empires and was used by merchants on trade excursions.[citation needed] From 1500 BCE, Indo-Iranian peoples started to enter in the region from Central Asia after having passed the Khyber Pass.[1][2]