Cita APA (7a ed.)

O'Kelly, M., Ryan-Enright, M., & Whelan, D. (1988). Discover our world: Environmental studies; nature, civics, science. Folens.

Cita Chicago Style (17a ed.)

O'Kelly, Mary, Mary Ryan-Enright, y Deirdre Whelan. Discover Our World: Environmental Studies; Nature, Civics, Science. Dublin: Folens, 1988.

Cita MLA (9a ed.)

O'Kelly, Mary, et al. Discover Our World: Environmental Studies; Nature, Civics, Science. Folens, 1988.