Origins of characters whose name contains “Absence (Una Nemo)”"

IssueTitleNotes
18Batman and RobinOrigin of Absence (Una Nemo)
Bk 4Batman and Robin1st Appearance of Absence (Una Nemo); Origin of Absence (Una Nemo); Collects Batman and Robin #1725
Bk 4/HCBatman and RobinHardcover; 1st Appearance of Absence (Una Nemo); Origin of Absence (Una Nemo); Collects Batman and Robin #1725