Cita APA (7th ed.)

Salvador, M. S., & Espiritu, I. (2013). When zero left number land. Adarna House.

Cita Chicago (17th ed.)

Salvador, Maita Songco, i Iori Espiritu. When Zero Left Number Land. Quezon City: Adarna House, 2013.

Cita MLA (9th ed.)

Salvador, Maita Songco, i Iori Espiritu. When Zero Left Number Land. Adarna House, 2013.