Name-Year (N-Y) System in CSE
CSE has three documentation systems which provide the same information, but in different formats:
Name-Year (N-Y) system: The author of the source and date of publication are placed in parentheses in the text, e.g., (Smith 2011). References are listed alphabetically in the Reference List. This system is very similar to APA style.
Citation-sequence (C-S) system: Each source cited in the paper is given a number the first time it appears in the text , e.g., 1. Anytime the source is referred to again, the text is marked with the same number. At the end of the paper, a list of references provides full publication information for each numbered source. Entries in the reference list are numbered in the order in which they are mentioned in the paper.
Citation-name (C-N) system: The reference list is alphabetized, and then numbered. These numbers are used in the text to cite the sources from the list, e.g., 1.
Format in-text References (Citation-Sequence Style)
The style advocated by CSE suggests that numbers appear in superscript, and appear before punctuation marks (commas or periods).
Example from The CSE Manual:
Traumatic life events and post-traumatic stress disorder (PTSD) are endemic among American civilians 1.
However, many scientific journals format these numbers differently, using square brackets or parentheses, or putting superscript numbers after the period.
Example from Communicative & Integrative Biology (2011):
The most fundamental specialization of the eusocial insects is the division of colony members into two castes, workers (functionally sterile individuals) and reproductives.1
Example from Current Opinion in Cell Biology (2012)
The classical cadherin system connects cadherins to the actin cytoskeleton via b-catenin and a-catenin to maintain tissue integrity in metazoans .
Example from mBio (2012):
Although xylem is considered a nutrient-limiting, low-oxygen environment (1), R. solanacearum is well adapted to it, growing to cell densities of 108 to 109 CFU/g stem while still remaining limited to xylem (2).
For consistency, the examples that follow have been reformatted to match CSE's preferred style (superscripted numerals before punctuation).
- In the citation-sequence system, sources are numbered by order of reference so that the first reference cited in the paper is 1, the second 2, and so on.
- In citation-name, the sources are numbered alphabetically so that 1 refers to the first source in an alphabetical list, 2 refers to the second source in that list, and so on.
When possible, put numbers immediately after the relevant word or phrase rather than at the end of a sentence.
Cite sources in tables and figures
Avoid using superscripted numerals in figures where they might be misconstrued as exponents. Instead, use superscripted letters like a,b for tables and figures. List them sequentially after all the text citations.
Content adapted from The Writing Center: The Writer's Handbook, CSE Citation-Sequence and Citation-Name Documentation
Formatting Parenthetical (In-Text) Citations | Name-Year Style
In-text citations consist of the last name of the author(s) and the year of publication. Enclose the name and year in parentheses without a comma, e.g., (Smith 2011).
An in-text reference should be placed immediately following the title, word, or phrase referring to the work.
Be sure that every in-text citation has a corresponding entry in the reference list (Exception: personal communications).
For multiple works published by an author in different years, place the years after the author name in chronological order, e.g., (Smith 1999, 2001)
For multiple works published by an author in the same year, add an alphabetic designator to the year in both your in-text citation and reference list, e.g., (Smith 1999a, 1999b)
For different authors with the same last name, provide initials or enough other names to distinguish between them, and separate them with a semicolon, e.g., (Smith BL 1999; Smith TD 2002)
For 2 authors, list both last names in the in-text citation separated by "and" (NOT "&"), e.g., (Haggarty and Gaynor 2008)
For more than 2 authors, list the first author's last name followed by "et al." and the year, e.g., (Coyne et al. 2001)
When the author is a corporation or other organization, you may use an abbreviated form of the name for your in-text citation, e.g., (TRU 2009). The abbreviation should appear in square brackets as the first part of the citation in your reference list.
If there is no author, include the first word(s) of the title (enough to identify the source) followed by an ellipsis (...), e.g., (Biological research ... 2007)
If there is no date of publication listed, include the words [date unknown] in square brackets.