APA (7th ed.) Citation

Citroen, P. R. Kleine Zeichenlehre.

Chicago Style (17th ed.) Citation

Citroen, Paul Roelof. Kleine Zeichenlehre. n. pl.

MLA (9th ed.) Citation

Citroen, Paul Roelof. Kleine Zeichenlehre.

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