Gaya APA

Leo, S., Benedicta, R, W. (2018). A challenging book to practice teaching in english (Ed. 1). Yogyakarta: CV. Andi Offset.

Gaya MLA

Leo, Sutanto., Benedicta, Rini, W.,. "A challenging book to practice teaching in english". Ed. 1 Yogyakarta: CV. Andi Offset, 2018. Text.