Update spec/section/fields.md

Co-authored-by: elsdvlee <[email protected]>

spec/section/fields.md

@@ -242,7 +242,7 @@ Note some columns in the table below have been shortened for brevity.
 
 A [=field=] MUST have a <!-- TODO reference to core reference formulation when available-->[reference formulation]() and an <!-- TODO reference to core iterator when available-->[iterator]() . 
 If no reference formulation is declared for a field, the reference formulation of the [=field parent=] is implied.
-If no iterator is declared for a field, a default iterator is implied. If the reference formulation of the field is `rml:JSONPath` or `rml:XMLPath`, the default iterator is the root of the document. Otherwise, the default iterator is a row.
+If no iterator is declared for a field, the default iterator of the field's reference formulation is implied.
 
 For the application of the <a data-cite="RML-Core#dfn-expressions">expression</a> of a [=field=] on the records of the [=field parent=], the parent's reference formulation is used, resulting in [=record sequence=] *R*. Afterwards the field's iterator is applied on this resulting record sequence *R* to obtain the [=field record sequence=] defined by the field.