+/**
+ * \brief
+ * \ref ElementSet is based on the STL map<> container
+ * (see \ref ElementSet::TagHT), as opposed to \ref SQItem
+ * which is based on an STL list container (see \ref ListDocEntry).
+ * It contains the 'zero-level- DocEntry (out of any Dicom Sequence)
+ */
+class GDCM_EXPORT ElementSet : public DocEntrySet