APA Style

Amos, J., Spenceley, A. (1998). I'm sorry! : maaf! . Yogyakarta, Indonesia: Penerbit Kanisius.

MLA Style

Amos, Janine., Spenceley, Annabel. "I'm sorry! : maaf!". Yogyakarta, Indonesia: Penerbit Kanisius, 1998. Text.