https://www.weforum.org/agenda/2021/05/covid-19-travel-tourism-virtual-reality/

https://www.travelpulse.com/news/tour-operators/perrillo-tours-offers-the-ultimate-agent-experience.html

https://www.travelresearchonline.com/blog/index.php/2021/04/perillo-tours-tries-live-video-tours-and-cooking-classes/

https://preferredmagazine.ca/perillo-tours-take-an-up-close-and-virtual-trip-to-italy-and-beyond/

https://www.forbes.com/sites/bernardmarr/2021/04/12/the-amazing-ways-vr-and-ar-are-transforming-the-travel-industry/?sh=67bda63336e0

https://www.travelweekly.com/Richard-Turen/It-may-be-virtual-but-it-sure-aint-reality

https://techxplore.com/news/2021-03-pandemic-fuels-boomin-virtual-reality.html