APA (7e ed.) Bronvermelding

Sparks, R. S. J., & Hawkesworth, C. J. (2004). The state of the planet: Frontiers and challenges in geophysics. American Geophysical Union International Union of Geodesy and Geophysics.

Chicago (17e ed.) Bronvermelding

Sparks, R. S. J., en C. J. Hawkesworth. The State of the Planet: Frontiers and Challenges in Geophysics. Washington, DC, [S.l.]: American Geophysical Union International Union of Geodesy and Geophysics, 2004.

MLA (9e ed.) Bronvermelding

Sparks, R. S. J., en C. J. Hawkesworth. The State of the Planet: Frontiers and Challenges in Geophysics. American Geophysical Union International Union of Geodesy and Geophysics, 2004.