- https://www.cati.com/blog/2016/05/rocket-science-is-easy-the-calculations/
- https://spaceflightsystems.grc.nasa.gov/education/rocket/rktpow.html
- https://en.wikipedia.org/wiki/Tsiolkovsky_rocket_equation
- https://en.wikipedia.org/wiki/Orbital_mechanics
- https://www.nasa.gov/audience/foreducators/k-4/features/F_Escape_Velocity.html
- http://www.rocketmime.com/rockets/qref.html
- https://www.sciencelearn.org.nz/resources/394-getting-rockets-into-space
- https://en.wikipedia.org/wiki/Orbital_spaceflight
- view-source:http://hyperphysics.phy-astr.gsu.edu/hbase/vesc.html#c2
- http://hyperphysics.phy-astr.gsu.edu/hbase/vesc.html#c2
- http://www.softschools.com/formulas/physics/escape_velocity_formula/90/
- http://www.softschools.com/formulas/physics/orbital_velocity_formula/76/