When writing a research paper or an article that contains references to GIS data, maps, or other geospatial material, it’s important to include a proper citation crediting the author of the GIS work.
Citations vary depending on if the map is a single piece of work, part of a map series, an atlas, or a map that is part of a book or a journal article. There are even specific citations if the map was created using GIS software or you are citing GIS data. There are varying citation guidelines for static web maps versus dynamic online mapping applications.
For each map, first consult the original work in order to extract the necessary information. Scan the map for the necessary information. If some of the needed citation information is not listed directly on the map, access any available background information. If the map is found within a book, article, or atlas, look for any figures or footnotes that provide additional detail. If the map is accessed from a web page, check for any background information on the source web site. Make sure you carefully note within your citation any missing information.
Unlike most books and journal articles, the map or GIS data being cited may not contain all the needed information for a full citation. The author can be either the name of the individual who created the map, or in the case where the individual is unknown, the name of the agency. If the map does not contain a title, use a descriptive sentence in lieu of the title. Put that sentence within brackets  to indicate that the title you are using is not an official title. Always note the scale if possible. If the scale is not provided on the map or is otherwise unknown, note this within the citation by stating “Scale Unknown.”
For all printed cartographic work, you will need to know the following: the author of the map, the title of the map, format in brackets (e.g. map, software, GIS data) the edition of the map (if available), the scale of the map, place of publication, the publishers, and the date.
Printed map references should be cited in the following order: Author. Title. [Format] Edition (if known). Scale. Place of publication: Publisher, Date.
Example: Sally James , Urban Forestry Management Plan for Gilford [Map]. 1:12,000. London, England: Map Publishers, 2010.
For a map found within a book, additional information about the book itself is appended to the citation. In parentheses after the map title, the format (usually map) is also added.
Map Author . Map title [format]. Scale. Place of publication: Publisher, Date. In: Book Author. Book title. Edition. Place of Publication: Publisher, Date, page.
Example: Sally James , Urban Forestry Management Plan for Gilford [map]. [1:12,000]. In: Maps About Gilford. London, England: Map Publisher, 2010.
Since many online sources have a tendency to be updated, when citing online map and GIS data sources, it’s important to list the URL and the date of the citation itself along with the actual publication date of the map. Many guidelines also suggest listing the data sources between the map citation and the software citation (not shown in this example).
Author. “Map title” [format]. Scale. “Title of the complete document or site”. Information date. URL – this should include the full path of the document address, not just the home page of the web site. (The date viewed)
Dempsey, Caitlin. Cartogram map of the distribution of billionaires based on citizenship [map]. Scale Not Given. “Geography of Billionaires: Mapping Nationalities and Residency.” March 2012. http://gislounge.com/geography-of-billionaires-mapping-nationalities-and-residency/. (September 24, 2012).
Maps created using a specific GIS software should have that information appended to the citation:
Author. “Map title” [format]. Scale. Edition. Place of production: Producer, Date of copyright or production. Using: Computer software title [format]. Edition. Place of production: Producer, Date of copyright or production.
Dempsey, Caitlin. Cartogram map of the distribution of billionaires based on citizenship [map]. Scale Not Given. “Geography of Billionaires: Mapping Nationalities and Residency.” March 2012. http://gislounge.com/geography-of-billionaires-mapping-nationalities-and-residency/. (September 24, 2012). Using: ArcGIS [GIS software]. Version 10.0. Redlands, CA: Environmental Systems Research Institute, Inc., 2010.
If you are citing an individual tool, cite the tools’ author, date of the too’s development, name of the tool, and URL. For example:
Beyer, H. L. 2004. Hawth’s Analysis Tools for ArcGIS. Available at http://www.spatialecology.com/htools.
There are several online resources that provide detailed examples of each instance of how maps, GIS data, and GIS software should be cited, depending on the originating publication of the work. The Arthur H. Robinson Map Library of the University of Wisconsin-Madison has a detailed list of map, GIS data, and GIS software citation instancesand how to cite those references, complete with example citations. Alberta Auringer Wood a member of the Bibliographic Control Committee of the Association of Canadian Map Libraries and Archives (ACMLA) has also compiled a similar list of “ACLMA Recommended Best Practices in Citation of Cartographic Materials” (PDF format).
Citing GIS Software and GIS Data
The guidelines above using universally accepted and documented styles of citing maps, GIS data, and GIS software. Individual GIS software makers also have their citation preferences. Aileen Buckley, Esri’s Mapping Center Lead, published a post on December 2, 2010 on “How to cite and use Esri Data“. In it, Esri takes a more legalese approach, requiring that cartographers first vet Esri sourced data for publication permissions and then suggested using the following for any maps created with its data:
“Maps throughout this book were created using ArcGIS® software by Esri. ArcGIS® and ArcMap™ are the intellectual property of Esri and are used herein under license. Copyright © Esri. All rights reserved. For more information about Esri® software, please visit www.esri.com.”
QGIS, the open source GIS software, has a suggested citation page for its software with the following listing for the QGIS project in general:
QGIS Development Team, <YEAR>. QGIS Geographic Information System. Open Source Geospatial Foundation Project. http://qgis.osgeo.org.
The GRASS GIS page also lists suggested citations:
GRASS Development Team, 2012. Geographic Resources Analysis Support System (GRASS) Software, Version 6.4.1. Open Source Geospatial Foundation. http://grass.osgeo.org.