Opinnion leadership material: story behind power balance links:
http://www.powerbalance.com/international
•http://www.iltasanomat.fi/ulkomaat/art-1288360210115.html
Reference group sources:
- Consumer Behaviour - Wayne D. Hoyer, Deborah J. MacInnis
- http://www.marketing91.com/reference-groups-in-consumer-buying/
- Lesson material – Raisa Varsta