File:Notre Dame of Paris' regulator lines.jpg

Regulating lines that give the Cathedral of Laon golden section.

LUND, Frederik Macody. Ad Quadratum. 1919. Sourcing to prove the Laon's Cathedral has golden ratio in its design.

The image comes originally from a book by Frederik Macody Lumd, 1919, so is PD in the US.

This image is in the public domain in the United States. In most cases, this means that it was first published prior to January 1, 1929 (see the template documentation for more cases). Other jurisdictions may have other rules, and this image might not be in the public domain outside the United States. See Wikipedia:Public domain and Wikipedia:Copyrights for more details. PD-US Public domain in the United States //en.wikipedia.org/wiki/File:Notre_Dame_of_Paris%27_regulator_lines.jpg

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