According to the type of historical value, references are defined as follows:

• for simple historical value - name of the object of Historical value type
• for one-column historical value - name of the object of Historical value type along with a row index. In ESL, a row index must be enclosed between square brackets (e.g. H.ColArchiv[2] (H.ColArchiv\HBJ,2,0))
• for structured historical value - name of the object of Historical value type along with a row index and a column name. List of columns is given by an object of Structure definition type, that defines the structure of the historical value. In ESL, such a reference is similar to the reference to an item of Structured variable type object (e.g. H.Struct[2]^ColName (H.Struct\HBJ,2,3)).