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 Yellow-billed shrike:

"

The species is resident in tropical Africa, south of the Sahara and north of the equator, but is not present in the Horn of Africa. It is present in Benin, Burkina Faso, Cameroon, Central African Republic, Chad, Congo, the Democratic Republic of Congo, Côte d'Ivoire, Gambia, Ghana, Guinea, Guinea-Bissau, Kenya, Mali, Mauritania, Niger, Nigeria, Senegal, Sierra Leone, South Sudan, Sudan, Togo, and Uganda.[1] It makes localised movements, but these have been little studied.[2]