1. Amazon.com. Amazon echo. https://www.amazon.com/echo/. Amazon.com. Amazon echo. https://www.amazon.com/echo/.
2. Google. Google home. https://store.google.com/product/google_home. Google. Google home. https://store.google.com/product/google_home.
3. Greg Sterling. Alexa devices maintain 70% market share in u.s. according to survey. https://marketingland.com/alexa-devices-maintain-70-market-share-in-us-according-to-survey-265180. Greg Sterling. Alexa devices maintain 70% market share in u.s. according to survey. https://marketingland.com/alexa-devices-maintain-70-market-share-in-us-according-to-survey-265180.
4. Robert Williams. Study: Smart speaker ownership surges 36% to 53m US adults. https://www.mobilemarketer.com/news/study-smart-speaker-ownership-surges-36-to-53m-us-adults/545717/. Robert Williams. Study: Smart speaker ownership surges 36% to 53m US adults. https://www.mobilemarketer.com/news/study-smart-speaker-ownership-surges-36-to-53m-us-adults/545717/.
5. Amazon. Alexa echo devices and your privacy amazon help & customer service. https://www.amazon.com/gp/help/customer/display.html?nodeId=GVP69FUJ48X9DK8V. Amazon. Alexa echo devices and your privacy amazon help & customer service. https://www.amazon.com/gp/help/customer/display.html?nodeId=GVP69FUJ48X9DK8V.