Inclusion in XML versus SGML

Hi Everybody !

	In SGML, you can do like thing in your DTD declaration :

		<!ELEMENT book (chapter,section) +(para) >

	This mean that that book contain a chapter and a section. The
chapter and section is composed by para.

	Now what I want to know, is how in XML I can declare such thing
(a repeating inclusion).

Thank you to help me !

Benoît Sévigny, Revenu Québec