76. The type attribute gives the styling language.
If the attribute is present,
its value must be a valid MIME type
that designates a styling language.
The charset parameter must not be specified.
The default value for the type attribute,
which is used if the attribute is absent, is "text/css"
参考:HTML Living Standard
(http://www.whatwg.org/specs/web-apps/current-work/multipage/semantics.html#the-style-element
http://www.whatwg.org/specs/web-apps/current-work/multipage/scripting-1.html#the-script-element)
The src attribute, if specified,
gives the address of the external script resource to use.
The value of the attribute must be a
valid non-empty URL potentially surrounded by spaces
identifying a script resource of the type given by the type attribute,
if the attribute is present,
or of the type "text/javascript", if the attribute is absent.
80. <!ELEMENT HTML O O (%html.content;)
-- document root element -->
<!ELEMENT DL - - (DT|DD)+ -- definition list -->
<!ELEMENT DT - O (%inline;)* -- definition term -->
<!ELEMENT DD - O (%flow;)* -- definition description -->
<!ELEMENT IMG - O EMPTY -- Embedded image -->
参考:strict.dtd
81. 形式 意味
A, B A, Bがこの順で
A&B A, Bが順不同で
+A 子孫にAが記述可能
-A 子孫にAが記述不可
82. <!ELEMENT HTML O O (%html.content;)
-- document root element -->
<!ENTITY % html.content "HEAD, BODY">
<!ELEMENT HEAD O O (%head.content;) +(%head.misc;)
-- document head -->
<!ENTITY % head.misc
"SCRIPT|STYLE|META|LINK|OBJECT“
-- repeatable head elements -->
<!ELEMENT BODY O O (%block;|SCRIPT)+ +(INS|DEL)
-- document body -->