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 T wave alternans:

This text has been unreferenced on Wikipedia for a very long time. If you can't find a source, be bold and remove it!

"

Patients who test MTWA positive or indeterminate for heart rate or dense ectopy (abnormal) should be referred to an electrophysiologist for further evaluation.[citation needed]