Columbia subject headings:
Harvard subject headings:
Compassion in literature.
Compassion--History--To 1500.
Greek drama (Tragedy)--History and criticism.
Mothers in literature
Passion-plays--History and criticism.
Sympathy in literature.
Theater--History--Medieval, 500-1500.
Princeton subject headings:
Compassion in literature.
Greek drama (Tragedy)--History and criticism.
Greek drama (Tragedy)--Themes, motives.
Passion-plays--History and criticism.