The picture says is all really..
The Le Corbusier Charles-Édouard Jeanneret-Gris French designer created the range which includes this LC3 armchair.
Read about the full life of the designers Le Corbusier here http://en.wikipedia.org/wiki/Le_Corbusier
Cassina have taken on the designs and reproduced them.
Your be able to find cheap copies of this LC3 along with the entire range of the Le Corbusiser designs but Cassina is the one and only to opt for.
High quality production is what cassina is famed for.
If you have been in a modern office is so likely you have already sat on a LC3 armchair on one of the LC sofas.