50 years of the Lego Brick.

MLA

Humberg, Christian. 50 Years of the Lego Brick. Königswinter: Heel Verlag, 2008.

APA

Humberg, C. (2008). 50 years of the Lego Brick. Königswinter: Heel Verlag.

Chicago

Humberg, Christian 50 Years of the Lego Brick. Königswinter: Heel Verlag, 2008.