In the Rubik's Cube, it has 8 corner pieces, 12 edge pieces, and 6 center pieces, therefore 8 + 12 = 6 = 26. What happened to the 27th piece since the cube has 27 pieces? - Quora
Disassembling a Rubik's cube | WikiCube | Fandom
How to take apart the Rubik's Cube and put it back together
Pièces détachées cube
Overview of Rubik's Cube and Reflections on Its Application in Mechanism | Chinese Journal of Mechanical Engineering | Full Text