The preceding axis
selects all elements that occur before the context node. The
preceding axis has no respect for hierarchy. The
first time it encounters an element's start tag, end tag, or
empty tag, it counts that element. For example, consider this
rule:
/descendant::BORN[position()=3]/preceding::*[position()=5]
This says go to the third BORN element from the root, Louise
Pauline Bellau's birthday, <BORN>29 Oct 1868</BORN>,
and then move back five elements. This lands on Maria Bellau's
PERSON element. There's no abbreviation for the
preceding axis.