Cita APA (7a ed.)

Hillstrom, K., & Hillstrom, L. C. (2003). Europe: A continental overview of environmental issues. ABC-CLIO.

Cita Chicago Style (17a ed.)

Hillstrom, Kevin, y Laurie Collier Hillstrom. Europe: A Continental Overview of Environmental Issues. Santa Barbara, Calif.: ABC-CLIO, 2003.

Cita MLA (9a ed.)

Hillstrom, Kevin, y Laurie Collier Hillstrom. Europe: A Continental Overview of Environmental Issues. ABC-CLIO, 2003.