Weingarten formula relative to 3D surface

http://dmentrard.free.fr/GEOGEBRA/Maths/Export5/WeingartMD.html
[url=http://dmentrard.free.fr/GEOGEBRA/Maths/Export5/WeingartMD.html]http://dmentrard.free.fr/GEOGEBRA/Maths/Export5/WeingartMD.html[/url]
– Daniel Mentrard

Information: Weingarten formula relative to 3D surface