golden ratio
explanation
The Golden Ratio (why it is so irrational) - Numberphile (youtube.com)
random
Wikidata
https://www.wikidata.org/wiki/Q41690
Wikimedia
https://commons.wikimedia.org/wiki/Category:Golden_ratio
Wikipedia
https://en.wikipedia.org/wiki/Golden_ratio
Wikiquote
https://en.wikiquote.org/wiki/Golden_ratio
