Understanding and Solving the Rubik's Cube Without Algorithms
11. References
Movement notations
http://worldcubeassociation.org/regulations/#notation
Frey and Singmaster's method
from: Handbook of Cubik Math; Alexander H. Frey, Jr. e David Singmaster, Hillside, New Jersey: Enslow Publishers, 1982. 193 p.
Commutators and Conjugates
http://www.ryanheise.com/cube/
App used for the interactive cubes