APA (7th ed.) Citation

Spyri, J. (2010). Heidi. Project Gutenberg.

Chicago Style (17th ed.) Citation

Spyri, Johanna. Heidi. To be supplied: Project Gutenberg, 2010.

MLA (8th ed.) Citation

Spyri, Johanna. Heidi. Project Gutenberg, 2010.

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