How to Cite a Map

Maps are among the harder sources to cite well, because the thing you read is almost never the thing the catalogue is named after. A national mapping series has one title, one publisher and one scale across hundreds of sheets; what identifies your source is the sheet or quadrangle number. Style manuals are also thin here: the fullest published templates come from university Harvard guides, and two of the five styles below have no map entry at all.

The worked example is a real map, verified on 22 September 2026 against the U.S. Geological Survey's own publication record and against Crossref: Geologic map of the Buckner 7.5-minute quadrangle, Louisa County, Virginia, by M. W. Carter and nine colleagues, published in 2025 as U.S. Geological Survey Scientific Investigations Map 3533 — one sheet at a scale of 1:24,000, with a 37-page pamphlet, DOI 10.3133/sim3533.

What to Collect

• The creator: a person, a team, or the mapping agency itself
• The title of the sheet, as printed on the map
• The year of publication or revision
• The sheet, quadrangle or plate number
• The scale, as a ratio (1:24,000, 1:50,000)
• The series the sheet belongs to (Explorer, Landranger, Scientific Investigations Map)
• The edition, where the sheet has been revised
• The publisher and, for Harvard, the place of publication
• A DOI where one exists; otherwise the URL and the date you consulted it

Quick Reference by Major Style

APA (7th Edition)

APA's own Common Reference Examples handout has no map entry, and neither does the University of Queensland Library's APA 7th guide. Murdoch University's APA guide does publish an Online Map entry, which is its example verbatim:

For a published sheet from a mapping agency, the closest APA form that is actually published is the report form in APA's handout — author, year, title, publisher, and the DOI or URL. Applied to the verified example, with the sheet number and scale carried in the title position where the publisher puts them:

In-text: (Carter et al., 2025)

This is an adaptation of APA's report form, not an APA map example, because APA does not publish one. Say so in a note if your marker asks. On listing ten authors, see citing multiple authors.

MLA (9th Edition)

The MLA Style Center has a post titled "How do I cite a map?", and it carries MLA's own banner: "This post relates to content in the eighth edition of the MLA Handbook." Check the ninth edition before relying on it. Its guidance is that a map is cited like any other work, by following the MLA template of core elements. Its free-standing print map example, verbatim:

And, if you do not call the work a map in your prose, MLA adds the medium in the final supplemental slot:

Applying the template to the verified example, with the series and sheet number in the supplemental slot:

In-text: (Carter et al.)

For a map that is a figure inside another work, MLA's post gives two options: refer to the map in your prose and cite the containing work, or treat the map as a work contained in another work. Its own examples of the first option are Fitz's Brazilian Narrative Traditions in a Comparative Context (Modern Language Association, 2005) and Kretzschmar's "GIS for Language and Literature Study" in Literary Studies in the Digital Age.

Chicago (18th Edition)

The Chicago Manual of Style is subscription-only. Its free Citation Quick Guide lists thirteen entries — book; chapter or other part of an edited book; translated book; book consulted in an electronic format; journal article; news or magazine article; book review; interview; thesis or dissertation; web page; social media content; video or podcast; personal communication — and a map is not among them. Murdoch University's Chicago author-date guide has no maps page either. There is therefore no free, citable Chicago map format. Ask your department which pattern it wants, and give the sheet number and scale whichever pattern you use.

Harvard (Cite Them Right)

Cite Them Right itself is behind a subscription, so the formats below come from two named university guides that publish Harvard templates: the University of Sheffield Library, whose guide states that it is based on Cite Them Right, and the University of York Library.

Sheffield's printed-map template and example, verbatim:

Sheffield's online-map template and examples, verbatim:

York publishes the same shape, with a bracketed [Map] label. Its template and example, verbatim:

Applying Sheffield's printed template to the verified example. Note what happens to the sheet-number slot: the USGS record describes this map as one sheet, and 3533 is the number of the item within the Scientific Investigations Map series, not a sheet number within a mapping grid. So the number goes in the series slot and the sheet slot is simply left out, rather than relabelling a series number as a sheet:

In-text: (Carter et al., 2025)

Ordnance Survey sheets are the other case: there the series (Landranger, Explorer) and the sheet number within it are two separate things, which is why Sheffield's and York's templates have a slot for each.

IEEE

The IEEE Reference Guide has no map section: its source-type sections are blogs, books, conferences, course materials, datasets, handbooks, lectures, legal citations, manuals, news articles, online video, patents, periodicals, reports, software, standards, theses, U.S. government documents, unpublished work and websites. Its nearest published example cites a topographic map under Report Online, and this is IEEE's own example, verbatim:

Following that pattern for the verified example:

In-text: [1]

Missing Elements

No sheet number. Tourist maps, historical maps and one-off thematic maps often have none. Say what the map is of and when it was published, and use the title to distinguish it.

No scale. Some sketch maps and web maps carry none. Sheffield's online template marks the scale as "if available"; leave it out rather than estimating it.

No named creator. Use the issuing agency as the author, which is what every template here does for Ordnance Survey and Google Maps. If there is no agency either, start with the title.

No date. Use the survey or revision date if the sheet carries one. If nothing does, use your style's undated convention: Sheffield's guide uses "(no date)" throughout, in the citation and in the reference alike.

No place of publication. Harvard templates ask for it and online records often omit it. Leave a visibly bracketed [Place of publication] slot and explain, rather than inventing a city.

Common Mistakes

• Citing the series but not the sheet, so the reader cannot tell which map you used
• Recording a scale as "1:24" or "24,000" — it is a ratio, and the whole ratio matters
• Citing the online viewer (Digimap, a tile server) as the publisher instead of the mapping agency
• Treating a map inside a book as a free-standing map: it is part of the book, with a page or figure number
• Citing a modern reprint of a historical map without saying which it is; give both the original survey date and the reprint
• Taking a Chicago or IEEE map format from a citation generator, when neither style publishes one

Sources for These Formats

• U.S. Geological Survey Publications Warehouse record for Scientific Investigations Map 3533 (its own recommended citation, sheet count, scale and DOI), pubs.usgs.gov, and the Crossref record for 10.3133/sim3533
• MLA Style Center, "How do I cite a map?", style.mla.org/citing-a-map/ — flagged by MLA as eighth-edition content
• Murdoch University Library, Chicago 18th author-date guide (checked for a maps page and found not to have one) and its APA guide, Online Map entry
• The Chicago Manual of Style Citation Quick Guide, chicagomanualofstyle.org — its thirteen entries, none of them a map
• University of Sheffield Library, "Harvard referencing" (based on Cite Them Right), Maps entry
• University of York Library, Harvard guide, Map entry
• IEEE Reference Guide, contents and the Report Online examples
• APA Style, Common Reference Examples handout (last updated 3 March 2026), checked for a map entry and found not to have one; University of Queensland Library APA 7th guide, likewise

Full style rules: APA, MLA, Chicago, Harvard, IEEE.