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 Charcot–Marie–Tooth disease:

"

Neurons, Schwann cells, and fibroblasts work together to create a functional nerve. Schwann cells and neurons exchange molecular signals by gap junctions that regulate survival and differentiation.[citation needed]