LEFTON, Irene F. Who Speaks for the Customer? : Improving Results with a Customer-Centered Framework. 1st Edition. New York : Routledge/Productivity Press Book, 2026. 358 s. Available on Internet: <https://ebookcentral.proquest.com/lib/euba-ebooks/detail.action?docID=32351677> ISBN 9781040692783.