| Attributes | att.dimensions (@unit, @quantity, @extent, @precision, @scope)  (att.ranging (@atLeast, @atMost, @min, @max)) 
                        
                           | cert | (certainty) signifies the degree of certainty associated with the intervention or interpretation. |  
                           | resp | (responsible party) indicates the agency responsible for the intervention or interpretation, for example an
                              editor or transcriber. 
                                 
                                    | Status | Optional |  
                                    | Datatype | 1–∞ occurrences of 
                                       separated by whitespace |  
                                    | Values | A pointer to an element in the document header that is associated with a person
                                       asserted as responsible for some aspect of the text's creation, transcription, editing, or
                                       encoding. |  |  
                           | evidence | indicates the nature of the evidence supporting the reliability or accuracy of the
                              intervention or interpretation. 
                                 
                                    | Status | Optional |  
                                    | Datatype |  |  
                                    | Suggested values include: | 
                                          internalthere is internal evidence to support the intervention.externalthere is external evidence to support the intervention.conjecturethe intervention or interpretation has been made by the editor, cataloguer, or
                                             scholar on the basis of their expertise.
                                           |  |  
                           | source | contains a list of one or more pointers indicating the sources which support the given
                              reading. 
                                 
                                    | Status | Mandatory when applicable |  
                                    | Datatype | 1–∞ occurrences of 
                                       separated by whitespace |  
                                    | Values | A space-delimited series of sigla; each sigil should correspond to a witness or
                                       witness group and occur as the value of the xml:id attribute on a
                                       witness or msDesc element elsewhere in the document. |  |  |