[1] Now A Robot Will Fill Your Car At The Gas Station, Here’s How It Works. Dec.13 2016. http://wonderfulengineering.com/now-a-robot-will-fill-your-car-at-the-gas-station-heres-how-it-works/
[2] Level luffing crane. Dec.13 2016. https://en.wikipedia.org/wiki/Level_luffing_crane