APA (7th ed.) Citation

(1991). Historische Stadtkerne in Nordrhein-Westfalen.

Chicago Style (17th ed.) Citation

Historische Stadtkerne in Nordrhein-Westfalen. Düsseldorf, 1991.

MLA (9th ed.) Citation

Historische Stadtkerne in Nordrhein-Westfalen. 1991.

Warning: These citations may not always be 100% accurate.