KMS uses whole text items as link sources. A linked item is denoted by a small circle to its left. Since a text item is normally surrounded by white space, the range of the link source is defined implicitly. Most linked items are at least one line of text, making them easy to select. Furthermore, text items can be as large as a full screen, thus allowing the author to provide as much semantic information about the link as is necessary.
Google-1
Google-2
»ThesaHelp: Copyright 1988 by the ACM