A list of acceptable pipe delimited values from which the document author must choose.

Note that in the example below, CHICKEN is assumed by default if no TYPE is specified.

<?xml version = "1.0"
         encoding="UTF-8"
         standalone = "yes"?>
<!DOCTYPE GROCERY_BASKET [
	<!ELEMENT GROCERY_BASKET ANY>
	<!ELEMENT MEAT EMPTY>
	<!ATTLIST MEAT (CHICKEN |
			BEEF |
			PORK |
			FISH) "CHICKEN">
	]>
<GROCERY_BASKET>
<MEAT TYPE = "FISH"/>
<MEAT TYPE = "BEEF"/>
<MEAT/>
</GROCERY_BASKET>