APA (7th ed.) Citation

Henk, R. (1990). Heidelberg. [s.n.].

Chicago Style (17th ed.) Citation

Henk, Richard. Heidelberg. [s.l.]: [s.n.], 1990.

MLA (9th ed.) Citation

Henk, Richard. Heidelberg. [s.n.], 1990.

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