# In-Text Citation Rules — Chicago Author-Date

## Placement

### Narrative Citations
Author surname(s) appear as part of the sentence. Year in parentheses after the surname(s) or integrated into the sentence.
- `According to Singh and Harris (2018)...`
- `In 2018, Singh and Harris reported...`

### Parenthetical Citations
Author surname(s) and year together in parentheses, placed at end of sentence before terminal punctuation (period).
- `This occurs frequently (Singh and Harris 2018).`

If positioned elsewhere in the sentence, the citation precedes any nonterminal punctuation (comma, semicolon).
- `This occurs frequently (Singh and Harris 2018); however...`

## Quoted Passages

A page number follows the year, separated by a comma:
- Short quote: `(Liu et al. 2009, 124)`
- Page range: `(Liu et al. 2009, 124–125)` (en dash, not hyphen)

Narrative citation with page: `Liu et al. (2009, 124) make the claim...`

### Block Quotes
Quoted passages of 40+ words: set in indented block form without quotation marks. Parenthetical citation after terminal punctuation.

### Multiple Quotes from Same Source in One Paragraph
Full parenthetical citation after the first quote; subsequent quotes from the same work use only page number in parentheses: `(127)`.

## Author Rules

### One Author
Surname and year: `Singh (2018)` or `(Singh 2018)`

### Two Authors
Both surnames, joined by "and": `Singh and Harris (2018)` or `(Singh and Harris 2018)`

### Three Authors
All three surnames: `Nowacki, Creech, and Parks (2020)` or `(Nowacki, Creech, and Parks 2020)`

### Four or More Authors
First author surname + "et al.": `Prinzie et al. (2009)` or `(Prinzie et al. 2009)`

### Organizational Authors
- If reference uses abbreviation: use abbreviation in citation: `NIAAA (2016)`
- If reference spells out full name: use full name: `National Institute on Alcohol Abuse and Alcoholism (2016)`

### No Credited Author
Short title in title case:
- Article/chapter titles: in quotation marks: `"Physician Oversight" (2019)`
- Book/report/website titles: italicised: `*Dual Disorders Recovery Book* (1993)`

### First Authors with Same Surname
Distinguish by adding given-name initials: `G. R. Smith et al. (2001)` and `T. J. Smith and Gladwell (2012)`

### Four+ Authors, Same First Author, Same Year
Extend surname list to show differences: `Parnell, Foster, et al. (2018)` and `Parnell, Klein, et al. (2018)`

## Publication Years

### Date Range
En dash, full second year: `(Author 2013–2019)`

### Forthcoming
`(Author, forthcoming)` — accepted but not yet published in any form

### No Date
`(Author, n.d.)` — no identifiable publication date

### Circa
`(Author, ca. 1920)` — estimated date

### Original Publication and Republication
Original year in square brackets: `(Dewey [1916] 1997)`

### Same Authors, Same Year
Lowercase letter designators: `(Murakami 2003a, 2003b, n.d.-a, forthcoming-a)`

## Multiple Citations

### In Parenthetical Unit
Arrange alphabetically by author surname. Semicolons separate different author lists:
`(Abbas and Ludden 2018; Carlyle 1997; 2015a, 76; 2015b; Carlyle et al. 1997; Federation of State Medical Boards 2000, n.d.; Piquant 2019, forthcoming)`

### Same Author List, Multiple Years
Author appears once, years in parenthetical units separated by commas (or semicolons if page numbers included):
`Carlyle (1997; 2015a, 76; 2015b)`

## Special Cases

### Multivolume Work Citations
- Single volume entry: cite normally
- Multi-volume entry: specify volume: `(Hauser 2005, vol. 2)` or with page: `(Hauser 2005, 2:110)`

### Secondary Resource Citations
`Huang and Zoller (1995, quoted in Zhu 2010, 18)` — only the primary resource gets a reference entry

### Personal Communication
`Tomi Adeyemi (pers. comm., September 3, 2014)` — no reference entry

### Tables and Figures
Citations usually in table footnotes, not body. In figure captions, not graphics.
