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Science reference style usually means the citation rules in Scientific Style and Format, published by the Council of Science Editors (CSE). It is not one format but three: citation-sequence, name-year and citation-name. They differ in how citations appear in the text and in how the reference list is ordered, while the entries themselves are nearly identical. Your journal or publisher decides which of the three you use.
This guide sets the three systems side by side, shows the same article and book reference in each, and points to the formats people often confuse with CSE. Everything on the systems comes from the Citation Quick Guide published with the manual (checked 2026-10-29).
What “science reference style” means
There is no single style called “science reference style”. The phrase is most often a search for CSE style, the format from the Council of Science Editors used in the natural sciences. The Council’s own tool describes Scientific Style and Format as presenting three systems for referring to references within the text of a journal article, book or other scientific publication. The abbreviated in-text references point to a list of references at the end of the document. For the organisation itself, see the CASRAI entry on the Council of Science Editors (CSE).
Two other readings of the phrase are possible. Some searchers want the format of a specific journal, and some want a medical or chemistry style. Those are different formats, covered in the table of alternatives below.
Who publishes it and which edition applies
The manual’s website, csemanual.org, lists the ninth edition, published in 2024 by the Council of Science Editors in cooperation with The University of Chicago Press (DOI 10.7208/cse9, checked 2026-10-29). The prior edition is the eighth, with text dated 2014.
The free Citation Quick Guide on scientificstyleandformat.org is labelled as the guide to the 8th edition (copyright 2014). The templates below come from that guide. If your journal asks for the current edition, check the entries against the ninth edition or your journal’s instructions for authors before submitting.
The three CSE systems compared
The quick guide states that the system of in-text references you use determines the order of references at the end of the document, and that the end references have essentially the same format in all three systems, except for the placement of the date in name-year.
| System | In the text | Order of the reference list |
|---|---|---|
| Citation-sequence | Numbers refer to the end references | In the sequence in which each reference first appears in the text; a repeat citation reuses the same number |
| Citation-name | Numbers refer to the end references | Alphabetical by author, then numbered in that order; the number stays fixed wherever the work is cited |
| Name-year | Author surname(s) and year of publication, for example (Smart et al. 2003) | Unnumbered, alphabetical by author and year; several works by one author in chronological order |
The quick guide adds that the manual itself uses citation-sequence for its own references, and that each system is widely used in scientific publishing. It also notes that name-year is sometimes called the Harvard system.
Reference list templates
These templates and sample entries are quoted from the 8th-edition quick guide. The sample authors are the guide’s own examples, not CASRAI claims.
Journal article
- Citation-sequence and citation-name: Author(s). Article title. Journal title. Date;volume(issue):location.
- Name-year: Author(s). Date. Article title. Journal title. Volume(issue):location.
The guide’s worked example, first in the numbered systems and then in name-year:
- Smart N, Fang ZY, Marwick TH. A practical guide to exercise training for heart failure patients. J Card Fail. 2003;9(1):49–58.
- Smart N, Fang ZY, Marwick TH. 2003. A practical guide to exercise training for heart failure patients. J Card Fail. 9(1):49–58.
Per the guide: separate the date from volume and issue by a semicolon (numbered systems), precede the location with a colon, and generally abbreviate journal titles according to the ISSN International Centre’s List of Title Word Abbreviations. For articles with more than 10 authors, list the first 10 followed by “et al.”
Book
- Citation-sequence and citation-name: Author(s). Title. Edition. Place of publication: publisher; date. Extent. Notes.
- Name-year: Author(s). Date. Title. Edition. Place of publication: publisher. Extent. Notes.
Example from the guide: Ferrozzi F, Garlaschi G, Bova D. CT of metastases. New York (NY): Springer; 2000. In name-year the same book reads Ferrozzi F, Garlaschi G, Bova D. 2000. CT of metastases. New York (NY): Springer. Extent and notes are optional.
Website
- Citation-sequence and citation-name: Title of Homepage. Edition. Place of publication: publisher; date of publication [date updated; date accessed]. Notes.
- Name-year: Title of Homepage. Date of publication. Edition. Place of publication: publisher; [date updated; date accessed]. Notes.
The guide says online references follow the same principles as printed ones, with an added update date, an access date and a URL. Chapter 29 of the manual holds the full set of examples.
Which system should I use?
- Open the journal’s or publisher’s instructions for authors. The Council’s guide says to consult your publisher to determine which system you need.
- If the instructions name a CSE system, use that one. If they name a numbered style without saying which, check a recent article from the same journal to see whether numbers follow order of appearance (citation-sequence) or alphabetical order (citation-name).
- If you are writing for a course or lab rather than a journal, use the system your instructor or lab specifies.
- Check the edition. The free quick guide is for the 8th edition; the current manual is the 9th.
- Pick the template for each source type from the section above and keep the same system throughout. Reference managers can apply a style automatically; see editing a CSL citation style.
Strengths and limits
- Strength: one set of reference entries serves three in-text systems, so switching systems mostly changes the order of the list and, in name-year, where the date sits.
- Strength: numbered systems keep the running text short, which the guide’s own choice of citation-sequence for the manual reflects.
- Limit: “CSE style” does not by itself tell a journal which system it wants. The choice belongs to the publisher.
- Limit: the free guide covers a subset of source types and the 8th edition. The full rules, including the Chapter 29 examples, sit in the manual.
Alternatives and look-alikes
If your journal does not ask for CSE, one of these related formats may be the one you need. Each row links to the CASRAI guide on that format. Open it for the rules of that style rather than assuming they match CSE.
| Format | CASRAI guide |
|---|---|
| Vancouver (ICMJE) | Vancouver referencing style: numbering rules, author format and templates |
| AMA (11th edition) | AMA citation style: how to format references |
| IEEE | IEEE reference format |
| ACS (chemistry) | Chemistry manuscript conventions in ACS style |
| Harvard (author-date) | Harvard reference list |
FAQ
Is science reference style the same as CSE style?
In most searches, yes. CSE is the Council of Science Editors format described in Scientific Style and Format. There is no separate official format named “science reference style”.
How many CSE citation systems are there?
Three: citation-sequence, name-year and citation-name, according to the manual’s own quick guide.
What is the difference between citation-sequence and citation-name?
Both use numbers in the text. In citation-sequence the list follows order of first appearance; in citation-name it is alphabetical by author and numbered in that order.
Is name-year the same as Harvard?
The guide says name-year is sometimes called the Harvard system. It describes the in-text form and list order; it does not claim identity with every Harvard variant.
Which edition should I cite?
The current edition is the ninth (2024). The free online quick guide is for the eighth. Follow the edition your journal names.
Sources
- Council of Science Editors, Scientific Style and Format Citation Quick Guide (8th edition), scientificstyleandformat.org, checked 2026-10-29.
- CSE Manual, ninth edition (2024), csemanual.org, checked 2026-10-29. DOI: 10.7208/cse9.
