1. Australian Mining; 2018. http://www.australianmining.com.au/caterpillar-introduces-latest-ultra-class-trucks/.
2. Cameron Balloons; 2017. http://www.cameronballoons.co.uk/products/extreme-ballooning/gas-balloon Accessed July 2019.
3. Hot air balloon engine;Edmonds;Renewable Energy,2009
4. The potential of balloon engines to convert the low grade heat in warm, saturated air to electrical energy;Edmonds;Sol Energy,2011
5. Electrek; 2017. https://electrek.co/2017/09/17/electric-dumper-truck-worlds-largest-ev-battery-pack/ Accessed July 2019.