Multi-reference annotations are annotations pointing to more than one reference, consisting of a dimension and associated tag.
Assembly: RevitAPI (in RevitAPI.dll) Version: 2015.0.0.0 (2015.0.0.0)
Multi-reference annotations can be used to label and dimension Rebar elements, and are labeled in the user interface as "Multi-rebar annotations". MultiReferenceAnnotation is the annotation object instance. This class includes a reference to the associated dimension and tag element.