Non-REM Sleep %28NREM%29
Here's your citation in American Psychological Association (APA) format:
Non-REM Sleep %28NREM%29. (n.d.). In Alleydog.com's online glossary. Retrieved from: https://www.alleydog.com/glossary/definition-cit.php?term=Non-REM+Sleep+%2528NREM%2529