ReferenceValue - AnalyticalGraphicsInc/czml-writer GitHub Wiki
This page describes the possible content of a CZML document or stream. Please read CZML Structure for an explanation of how a CZML document is put together.
Represents a reference to another property. References can be used to specify that two properties on different objects are in fact, the same property.
Type: string
Examples:
"object1#billboard.scale"