Geology Research Guide

AGU follows American Psychological Association (APA) style on grammar, punctuation, table formatting, citations, and references. This full guide includes basic APA style (and exceptions) and AGU-specific style. We also offer a Brief Guide to AGU Style and Grammar.

For detailed information, see Publication Manual of the American Psychological Association, Sixth Edition.

Please note that all sources cited in text, tables, and figures must appear in the reference list, and all entries in the reference list must be cited in text. References that are only cited in supporting information should also be included in the reference list of the paper and cited in text. Data sets that are not newly reported as part of this research should also be cited in the references.

Text citations. In-text should be cited using author surname(s) and the date of publication:

“in earlier studies (Johnson, 2009)” or “…as given by Johnson and Smith (2008)” or “In 2012, Johnson and Smith’s study showed that”

Note that author names are not italicized and a comma follows the author name(s) if the reference is enclosed in parentheses. If a multiple-author citation is in the running text, use the word “and”; if in a parenthetical citation, use the ampersand:

Zhu and Zhang (2016) found that….

A subsequent study found that… (Zhu & Zhang, 2016).

For references by three or more authors, use “et al.” after the first author: (Zhang et al., 2005). Please note, this is a deviation from APA style which lists all author names in works by three to five authors in the first citation in text and “et al.” in subsequent citations.

Reference entries should be ordered alphabetically by the last name of the first author. Follow a strict letter-by-letter alphabetization of the entire last name, ignoring spaces in surnames with multiple words (Lefer before Le Pichon, Vander Linden before van Giessen). When alphabetizing surnames, consider that “nothing precedes something” e.g., Brown before Browning. Other examples: Sanders before St. Amant, MacMillian before McArthur—i.e., alphabetize them literally, not as if they were spelled out.

Article in Journal

Fang, X., Liemohn, M. W., Nagy, A. F., Luhmann, J. G., & Ma, Y. (2009). On the effect of the Martian crustal magnetic field on atmospheric erosion. Icarus. Advance online publication. https://doi.org/10.1016/j.icarus.2009.01.012

Wang, C. (2005). A modeling study of the response of tropical deep convection to the increase of cloud condensational nuclei concentration: 1. Dynamics and microphysics. Journal of Geophysical Research: Atmospheres, 110, D21211. https://doi.org/10.1029/2004JD005720

Book and Reports

Moridis, G. J. (1998). A set of semianalytical solutions for parameter estimation in diffusion cell experiments (Rep. LBNL-41857). Berkeley, CA: Lawrence Berkeley National Laboratory.

U.S. Department of Health and Human Services, National Institutes of Health, National Heart, Lung, and Blood Institute. (2003). Managing asthma: A guide for schools (NIH Publication No. 02-2650). Retrieved from http://www.nhlbi.nih.gov/health/prof/lung/asthma/asthsch.pdf

Map/Thesis/Dissertation

Bentor, Y., & Vroman, A. (1959). Arava Valley, with explanatory text. In The geological map of the Negev (rev. ed., Sheet 19, scale 1:1,000,000). Jerusalem: Government Printer.

Liu, X. (2017). Surface energy and mass balance model for Greenland Ice Sheet and future projections, (Doctoral dissertation). Retrieved from Deep Blue. (http://hdl.handle.net/2027.42/137047). Ann Arbor, MI: University of Michigan.

Data Sets

Hall, D. K., G. A. Riggs, and V. V. Salomonson (2000), MODIS/Terra Snow Cover 5-Min L2 Swath 500m, Version 4, October 2007 to April 2008, http://nsidc.org/data/mod10_l2.html, Natl. Snow and Ice Data Cent., Boulder, Colo. (Updated daily.)