<sli> element is an item in a simple list (<sl>).
Simple list items have phrase or text content, adequate for describing
package contents, for example. When a DITA topic is formatted for
output, the items of a simple list should be placed each on its own
line, with no other prefix such as a number (as in an ordered list)
or bullet (as in an unordered list).
See appendix for information about this element in OASIS document type shells.
See sl .