Different kinds of reference styles

Depending on the way in which they record sources, scholarly reference styles can be divided into three main categories: documentary notes styles, parenthetical (or author-date) styles, and numbered styles. Within each category there are several, slightly different reference styles.

The different categories are described below. For information about specific reference styles, see

Documentary note styles

In documentary note styles (documentary-note citation systems), references are given in footnotes or endnotes. The notes are indicated by digits, which then recur with the full reference at the bottom of the page (footnote) or after the entire text (endnote). The digit is usually placed after the full stop ending the sentence to which the reference belongs.

Oxford and MHRA are documentary note reference styles.

Example: Documentary notes style (click to expand/contract)

The following example comes from an article about China during the Cultural Revolution in a journal called Politics, Religion & Ideology.


When he launched his great pre-emptive stab at the spectre of revisionism in 1966, Mao did so by playing the 'mass' card. China's Minister of Public Security, close to Mao at the time and speaking about the so-called 'vanguard of the masses' – Beijing's Red Guards – told police officers in August 1966 not to:

say it is wrong of them to beat up bad persons: if in anger they beat someone to death then so be it. If we say it is wrong then we'll be supporting bad persons. After all, bad persons are bad, so if they're beaten to death it is no big deal!5

But who were the 'masses'? How could one tell them apart from what, in a different discursive realm, would have been identified as the 'anti-masses'? Four months later, Kang Sheng – a member of the Politburo Standing Committee described by his foreign biographers as Mao's 'evil genius'6 – spelled out the heuristic rule-of-thumb to be employed to tell the apparent from the real 'masses': 'Whoever opposes [CCP Vice-Chairman] Lin [Biao] or Chairman Mao is a counter-revolutionary. They are not the masses, but the enemies of the masses'.7

[From endnote section of the article:]

5. Beijing shi huaxue gongyeju jiguan hongse xuanchuanzhan, ed. Wuchanjieji wenhua dageming ziliao (Materials on the Great Proletarian Cultural Revolution), 4 vols (Beijing, 1966), Vol. 2, p.192.
6. John Byron and Robert Pack, The Claws of the Dragon: Kang Sheng – The Evil Genius Behind Mao – and His Legacy of Terror in People's China (New York: Simon & Shuster, 1992).
7. Shoudu dazhuan yuanxiao hongweibing daibiao dahui Zhengfa gongshe, ed., Zhongyang fuze tongzhi guanyu wuchanjieji wenhua dagemingde jianghua (Speeches by Responsible Comrades from the Centre on the Great Proletarian Cultural Revolution), 2 vols (Beijing, 1967), Vol. 2, p.109.

(Schoenhals, 2008, pp. 4, 16-17)

Comment: References are indicated by superscripted numerals and the full references are then given in endnotes. The numbered reference style used by this journal is presented on their website:

Parenthetical styles or author-date styles

In parenthetical, or author-date styles, in-text references are given within parentheses before the full stop of the sentence containing the reference.

APA, Harvard, and MLA are parenthetical reference styles.

Example: Parenthetical style (click to expand/contract)

The example below comes from an article in Advances in Cognitive Psychology about music performance anxiety in young musicians.


Osborne and Kenny (2005a) also found that MPA [Music Performance Anxiety] was more specifically related to social anxiety than trait anxiety with stronger positive correlations between the MPAI-A and social phobia measures than MPAI-A and trait anxiety. Results on the Social Phobia Anxiety Inventory for Children (SPAI-C; Beidel et al., 1998) indicated potentially higher rates of social phobia diagnosis (between 6% and 21%) than those found in most adolescent community samples (between 1% and 2%) (Anderson, Williams, McGee, & Silva, 1987; Essau, Conradt, & Petermann, 1999; Kashani & Orvaschel, 1990; Maroon, 2003).  

(Kenny & Osborne, 2006, p. 107)

Comment: The parenthetical reference system APA is used. Last names of authors of works referred to plus their publication year are provided in parenthetical references. A list of references, where full bibliographic details are given, is then supplied at the end of the article. The author-date reference style used by this journal is presented on their website:

Numbered styles

In numbered styles, sources are referred to with Arabic numbers within square brackets or in superscript, and the references are listed in a numbered reference list after the text. References are numbered in the order in which they first appear in the text.

Vancouver and IEEE are numbered styles.

Example: Numbered style (click to expand/contract)

The example below comes from the IEEE Transactions on Biomedical Circuits and Systems. It is the opening of an article about loudspeakers for digital hearing aids.


Previous studies of anatomy, physiology, and psychophysics have contributed to a growing curiosity about normal versus impaired auditory systems [1]–[3], attracting the benefits of hearing aids for the hearing impaired [4], [5]. Approximately 28 million Americans have hearing impairments. Hearing loss affects nearly 17 in 1 000 children under the age of 18, and the incidence increases with age: nearly 314 in 1 000 people over age 65 have hearing loss. According to recent statistics, however, 80% of those who could benefit from a hearing aid chose not to use one. The reasons for the number of untreated cases include reluctance to recognize hearing loss and common misconceptions about hearing aids, such as a social stigma to wearing them. People find hearing aids inconvenient, and some accept that losing hearing capability is a part of aging, known as presbycusis [6], [7].

[From References:]

[1] L. Squire, H. Schmolck, and S. M. Stark, "Impaired auditory recognition memory in amnesic patients with medial temporal lobe lesions," Learning Memory, vol. 8, no. 5, pp. 252–256, 2001.
[2] C. Duncan, "Psychophysics and psychology hearing," Amer. J. Psychol., vol. 92, no. 2, pp. 377–379, 1979.
[3] B. Moore, "Psychophysics of normal and impaired hearing," British Med. Bull., vol. 43, no. 4, pp. 887–908, 1987.
[4] J. Dianne, "Hearing loss, speech, and hearing aids," J. Speech Hearing Res., vol. 36, pp. 228–244, 1993.
[5] P. Kricos, S. Lesner, and S. Sandridge, "Expectations of older adults regarding the use of hearing aids," J. Amer. Academy Audiol., vol. 2, pp. 129–134, 1991.
[6] G. Gates and J. Mills, "Presbycusis," Lancet, vol. 366, no. 9491, pp. 1111–1120, 2005.
[7] J. Cohen-Mansfield and J. Taylor, "Hearing aid use in nursing homes. Part 2: Barriers to effective utilization of hearing aids," J. Amer. Med. Dir. Assoc., vol. 5, no. 5, pp. 289–296, 2004.

(Je, S-S, Rivas, F., Diaz, R. E., Kwon, J., Kim, J., Bakkaloglu, B., Kiaei, S. & Chae, J., 2009, pp. 348, 357)

Comment: References are provided in the form of Arabic digits within square brackets. The full references are then listed (in the order in which they appear in the text) at the end of the article. On the journal's website, instructions for authors are available. The reference style used in this example is IEEE.