(1993). D.D.R. Collectors reference guides. Oliver.
Cita Chicago (17th ed.)D.D.R. Collectors Reference Guides. Eton Wick: Oliver, 1993.
Cita MLA (8th ed.)D.D.R. Collectors Reference Guides. Oliver, 1993.
Atenció: Aquestes cites poden no estar 100% correctes.