Strict Level 1 HTML DTD
This document type declaration refers to the level 1 HTML DTD with the "HTML.Recommended" entity defined as "INCLUDE" rather than "IGNORE;" that is, it refers to the more structurally rigid definition of HTML.
<!-- html-1s.dtd Document Type Definition for the HyperText Markup Language Struct Level 1 $Id: html-1s.dtd,v 1.3 1995/06/02 18:55:43 connolly Exp $ Author: Daniel W. Connolly <connolly@w3.org> See Also: http://www.w3.org/hypertext/WWW/MarkUp/MarkUp.html --> <!ENTITY % HTML.Version "-//IETF//DTD HTML 2.0 Strict Level 1//EN" -- Typical usage: <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML Strict Level 1//EN"> <html> ... </html> -- > <!-- Feature Test Entities --> <!ENTITY % HTML.Recommended "INCLUDE"> <!ENTITY % html-1 PUBLIC "-//IETF//DTD HTML 2.0 Level 1//EN"> %html-1;