"Newton shell theorem" - ???

Hi guys.
Who know physics, help please!
The Newton Shell Theorem - ( Shell theorem - Wikipedia, the free encyclopedia ) - how does this thing named in Russian?

Теорема Ньютона о гравитационных эффектах тонкой сферической оболочки. ??

It seems Newton did not use this phrase 'Shell Theorem', but all physics profs do.
In Principia, it is is theorems XXX and XXXI of book I section XII. Physics profs have 'telescoped' the two theorems into one, since they are the two cases of a body inside and outside a thin spherical shell.
http://17centurymaths.com/contents/newton/book1s12.pdf
.Whole Principia:
http://17centurymaths.com/contents/newtoncontents.html.
.
You can check them out in Russian: (Переводы на русский язык)
Математические начала натуральной философии — Википедия.
.How to name in Russian?
Теоремы XXX и XXXI книги I раздела XII о гравитационных эффектах тонкой сферической оболочки.??

Thank you a lot, Seraph!

In russian scientific literature its doesn't shaped in separate theorem - I dont know, why.

I found this as practice problem in one book.

The proof for the one about gravitation inside the shell is very much like the one for electrostatic force inside closed sphere.

And so what is the gravity at the center of the earth?

By the way, when those physicists and mathematician say 'Principia' they mean Newton's big book. (The c is pronounced as a k for Principia.)