APA (7th ed.) Citation

Hertel, H. (1969). Die Flechtengattung Trapelia Choisy ([Sonderdr.].).

Chicago Style (17th ed.) Citation

Hertel, Hannes. Die Flechtengattung Trapelia Choisy. [Sonderdr.]. 1969.

MLA (9th ed.) Citation

Hertel, Hannes. Die Flechtengattung Trapelia Choisy. [Sonderdr.]. 1969.

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