APA (7th ed.) Citation

De Graaf, A., Molan, C., & Spyri, J. (1997). Heidi (Philippine ed.). St. Pauls.

Chicago Style (17th ed.) Citation

De Graaf, Anne, Chris Molan, and Johanna Spyri. Heidi. Philippine ed. Makati City: St. Pauls, 1997.

MLA (9th ed.) Citation

De Graaf, Anne, et al. Heidi. Philippine ed. St. Pauls, 1997.