APA (7th ed.) Citation

Spyri, J. (1956). Heidi. Puffin Books.

Chicago Style (17th ed.) Citation

Spyri, Johanna. Heidi. Puffin Books, 1956.

MLA (8th ed.) Citation

Spyri, Johanna. Heidi. Puffin Books, 1956.

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