(1989). Lutz Brockhaus: Katalog 1989/90.
Cita Chicago (17th ed.)Lutz Brockhaus: Katalog 1989/90. Berlin, 1989.
Cita MLA (8th ed.)Lutz Brockhaus: Katalog 1989/90. 1989.
Atenció: Aquestes cites poden no estar 100% correctes.
(1989). Lutz Brockhaus: Katalog 1989/90.
Cita Chicago (17th ed.)Lutz Brockhaus: Katalog 1989/90. Berlin, 1989.
Cita MLA (8th ed.)Lutz Brockhaus: Katalog 1989/90. 1989.