public void AddSecondaryField(Field field)
 {
     this.SecondaryFields.Add(field);
 }
 public void AddPrimaryField(Field field)
 {
     this.PrimaryFields.Add(field);
 }
 public void AddBackField(Field field)
 {
     this.BackFields.Add(field);
 }
 public void AddHeaderField(Field field)
 {
     this.HeaderFields.Add(field);
 }
 public void AddAuxiliaryField(Field field)
 {
     this.AuxiliaryFields.Add(field);
 }