[1] Dimension elements occur as children of . Valid tag names are constrained to the set of dimension names identified in the set attribute of the parent element. For any given dimension name in the set, zero or one occurrences are allowed within a element. [Annotation] 
Occurrence
D e f i n i t i o n
C h i l d r e n
A t t r i b u t e s
O c c u r r e n c e
A n n o t a t i o n