Joy Goodman Philip D. Gray Kartik Khammampad Stephen A. Brewster Using Landmarks to Support Older People in Navigation. 38-48 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=3160&spage=38 2004 conf/mhci/2004 Mobile HCI db/conf/mhci/mhci2004.html#GoodmanGKB04