Introduction

A citation style is a set of rules citing sources in academic writing. Whenever you mention someone else’s work, a citation is needed to avoid plagiarism. Different citation styles have different rules for in-text citations, bibliographic entries and paper drafting. The differences can be very subtle, so it is important to carefully examine the style rules you use. In-text citations refer to a source (for example, by citations or paraphrasing), you must add a citation in the text. There are three main types of citation; (1) Parental citations, you put the source reference in parentheses directly in your text. It usually includes the author’s last name along with the publication date and/or page number. (2) Note citation, you put a reference to the source in a footnote or endnote. (3) Numeric citations, you give the number of each of your sources. When you want to cite a source, use the bibliography and the correct number. Reference list entries, include at the end of your paper and list all the sources you cite. Each entry in the list corresponds to an in-text citation, and gives the reader complete publication information to easily find the source.Footnote 1 Citing its sources is an extremely important component of its research project. It shows that you are a responsible researcher and that you have located appropriate and reputable sources that support your thesis or claim. Also, if your work is being posted online or in print, there is a chance that others will use your research project in their work.Footnote 2 There are various cited styles namely MLA, APA, AIP, Chicago, IEEE, MHRA, CISRO, Harvard, Vancouver etc.

1. Modern Language Association (MLA) style: MLA is an organization that focuses on language and literature. The MLA format is mainly used for language, literature, liberal arts and other humanities subjects.Footnote 3 MLA has been widely adopted by scholars, professors, journal publishers, and both academic and commercial process across the world.Footnote 4 The MLA format follows the author-page method of in-text citations. This means that the author’s last name and page number(s) are taken from a quote or parapress that should appear in the text, (such as Smith 173) and a complete reference should be quoted on the work page.Footnote 5 In-text citations include general information (author’s surname and page number), or just (page number) if the author’s name is in the sentence. No comma and ‘p’ or ‘pg’ are required. The reference appears in parentheses at the end of the sentence that includes a reference or quote from your source. The citation is followed by a punctuation mark. A complete reference to the resource should then be included in the cited work page at the end of the essay.Footnote 6,Footnote 7

Examples: Article in Print Journal

Author’s Last name, First name. “Title of Source”. Title of Container, other contributors, version, numbers, publisher, publication date, location (see footnote 3).

Hannah, Daniel K. “The Private Life, the Public Stage: Henry James in Recent Fiction.” Journal of Modern Literature, vol. 30, no. 3, 2007, pp. 70–94.Footnote 8

Example: Internet database/webpage.

Bennish, Steve, and Laura A. Bischoff. “Voters Support Ohio Library Building Boom”. Dayton Daily News, 24 June 2016. Ebscohost,http://search.ebscohost.com.i.ezproxy.nypl.org/login.aspx?direct=true&AuthType=cookie,ip,url,cpid&custid=nypl&db=nfh&AN=2W63144501246&site=ehost-li.

2. American Psychological Association (APA) style: APA style is most frequently used within the social sciences, in order to cite various sources.Footnote 9 The APA referenced style is an “author-date” style, so the author(s) in citation in the text and the year of publication are given in full or partially rounded brackets (Smith and Bruce, 2018). Use only the author’s name after the comma and the year of publication. Include page, chapter or section number.Footnote 10,Footnote 11

Example: Article in Print Journal

Pandey, S. (2012). Prevalence of factor V Leiden G1691A, MTHFR C677T and prothrombin G20210A among Asian Indian sickle cell patients. Clinical and Applied Thrombosis/Hemostasis, 18(3), 320–323. https://doi.org/10.1177/1076029611425830

Example: Internet database/webpage

Harris, J. G. The return of the witch hunts. Witchhunt Information Page. Retrieved May 28, 1996, from http://liquid2-sun.mit.edu/fells.short.html.

3. Chicago style: Unlike many citation styles, Chicago gives authors two different ways to source documents; Author-Date System and Notes-Bibliography (NB) System.Footnote 12 As its name suggests, author-date uses ancestral citations in the text to refer to the author’s last name of the source and the year of publication. Each parenthetical citation corresponds to an entry on a reference page that concludes the document. In these respects, author-date, for example, is similar to the APA genre. In contrast, NB directs the reader to a brief citation at the bottom of the page, using the numbered footnote of the text. This corresponds to a complete citation on a bibliographic page that concludes the document.Footnote 13

Example: (In text citation)

Cole found that “The bones were very fragile” (see footnote 1).

Each superscript then refers to a numbered citation in the footnotes or endnotes.

Journal Article:

First Name Last Name of Author, “Article Title,” Journal Name Volume Number, no. of issue (Date published): Page-Range, DOI address.

Sanjay Pandey, “Genotypic Influence of α-Deletions on the Phenotype of Indian Sickle Cell Anemia Patients” The Korean Journal of Hematology 46, no. 3 (Korean Society of Hematology 2011):192–195, http://dx.doi.org/10.5045/kjh.2011.46.3.192

Example- Internet database/webpage

Full Notes:

U.S. Census Bureau. Immigration by Leading Country or Region of Last Residence: 1901 to 2001, accessed January 28, 2006, http://www.census.gov/statab/hist/HS-09.pdf.

Bibliography:

U.S. Census Bureau. Immigration by Leading Country or Region of Last Residence: 1901 to 2001, accessed January 28, 2006. http://www.census.gov/statab/hist/HS-09.pdf.

4. Vancouver style: The Vancouver style is often used in medicine and natural sciences and sometimes in technology.Footnote 14 The Vancouver style is mainly known as recommendations for publishing scholarly work in medical journals (ICMJE recommendations). It was developed in Vancouver by editors of medical journals in 1978 and more than 1000 medical journals (including ICMJE members BMJ, CMAJ, JAMA and NEJM) used this style.Footnote 15 Vancouver style follows the rules of International Committee of Medical Journal Editors, which is maintained by the US National Library of Medicine.Footnote 16

Example: Article in Print Journal

Pandey S, Ranjan R, Mishra RM. Interaction of—α 3.7, ß thalassemia mutation IVS 1-5 and HbD Punjab in a family: a case report. Ind J Clin Biochem. 2012 Sept; 27(3):314–317.

Example: Internet database/webpage

Body weight. 2012. MedlinePlus Available: http://www.nlm.nih.gov/medlineplus/bodyweight.html [Accessed 16.01.2013]

5. Harvard style: The Harvard (Author-Date) citation style is a system that students, authors, and researchers can use to incorporate other people’s quotes, discoveries, and ideas into their work so that their conclusions are violated without violating any intellectual property rules. The popular format is commonly used in assignments and publications for the humanities as well as the natural, social and behavioural sciences.Footnote 17

In-text citation: It mainly consists of round brackets placed within the text of the authors’ last names and year of publication (and page numbers if it is quoted directly). If there is no thoughtful author, the title and date are used.

Reference list: The reference list should be sorted alphabetically by the last name of the first author of each work. A reference to an author is ordered alphabetically by the first key word of the title. Use only the initial letters of the authors’ given names. No full stop and space between initials. Last name comes first.Footnote 18

Example: Reference list print journal article

Conley, TG & Galeson, DW 1998, ‘Nativity and wealth in mid- nineteenth century cities’, Journal of Economic History, vol. 58, no. 2, pp. 468–493

In-Text Example (Conley and Galeson 1998).Footnote 19

Example: Internet database/webpage

Cancer Council 2017, Causes of cancer, Cancer Council, viewed 21 May 2018, https://www.cancer.org.au/about-cancer/causes-of-cance.

6. American Institute of Physics (AIP) style: The AIP style is established by the American Institute of Physics. AIP is a commonly used format in the field of physics. AIP is a numbered style in which references counted in order of appearance of the article and listed in that order at the end of the article.Footnote 20 The journals title should be Abbreviated and eliminate words like “of” or “the”.Footnote 21 Few example of common abbreviations are: Journal (J.), Medical (Med.), Research (Res.), Clinical (Clin.), Laboratory (Lab.), Analysis (Anal.). This means “Journal of Medical Research” would be abbreviated “J. Med Res.” and “ Clinical Laboratory Analysis “ would be abbreviated “ Clin. Lab. Anal.”

Example:

A.A. Surname and B.B. Surname, Abbreviated title of journal. volume no, issue or part of (in brackets if needed), First page number of the article (year of publication).Footnote 22

G. Young and R.E. Funderlich, J. Appl. Phys. 44, 5151 (1973)

Example: Internet database/webpage

T.M. Huber, How To Locate Material for Formal Reports, WWW Document, (http://physics.gac.edu/~huber/misc/finding.htm).

7. Commonwealth Scientific and Industrial Research Organization (CSIRO) style: The CSIRO style based on the Australian Journal of Botany referring style that is published by CSIRO. It follows the author-date citation within the text of the document, e.g. (Pandey 2019), and the detailed reference list at the end of the document.Footnote 23

Example: Article in Print Journal

Harper, M. J., McCarthy, M. A., and van der Ree, R. (2005). The use of nest boxes in urban natural vegetation remnants by vertebrate fauna. Wildlife Research32, 509–516.Footnote 24

Example: Internet database/webpage

U.S. Geological Survey (2015) ‘Earth Explorer’. Available at http://earthexplorer.usgs.gov [Verified 12 September 2015]

8. Australian Guide to Legal Citation (AGLC) style: AGLC style is designed to identify legal sources which follow the footnote citation system specifically. It is not related to the legal writing style. The AGLC is moderately neutral, meaning that it allows a resource to be cited in a consistent manner, whether it is published in print or online in a report or unproven format.Footnote 25

Example: Article in Print Journal

Author’s First Name Surname, ‘Title of article’ ({Year}) Volume (Issue) Journal Name Starting page, Pinpoint.Footnote 26

Belindia Bennett, Terry Carney and Caroline Saint, ‘Swine Flu,Doctors and Pandemics: Is there a Duty to Treat during a Pandemic?’ (2010) 17(5) Journal of Law and Medicine 736, 738.

Example: Internet database/webpage

Footnote:

International Whaling Commission, IWC Information (4 August 2010) <http://www.iwcoffice.org/commission.iwxmain.htm>.

Bibliography:

International Whaling Commission, IWC Information (4 August 2010) <http://www.iwcoffice.org/commission.iwxmain.htm>.

9. Modern Humanities Research (MHRA) style: The MHRA referencing is a style of reference developed by the Association of Modern Humanities Research. It is primarily intended for use in relation to books and journals published by the association but is also used by students in a wider context.Footnote 27 The MHRA style is often used in the arts and humanities. It uses footnotes that refer solely to a citation. Footnoting is the major advantage of MHRA: a reader does not need to consult the bibliography to find references, because the footnote provides all the details.

A. Footnotes

  1. I.

    Sequential superscript numbers should be used to indicate a footnote in the essay’s text (see footnote 1).

  2. II.

    A corresponding superscript number must be used at the beginning of the footnote

  3. III.

    Always give full reference when first citing a source

  4. IV.

    Subsequent footnotes from the same source should include the authors last name (where possible), volume number (if relevant) and page number/s

  5. V.

    Subsequent footnotes with no author should include the source title, volume number (if relevant) and a shortened version of the page number / s.

  6. VI.

    When more than one source is cited by the same author or more than one author with the same last name, subsequent footnotes include authors with last name, shortened version of source title, volume number (if relevant) and should include the page number/s. (Use only the short title of one source to refer to more than one work by the same author or citing multiple authors with the same last name).

B. Bibliography

  1. I.

    Arrange alphabetically.

  2. II.

    If there is more than one source by the same author arrange by authors last name then in alphabetical order of the title, disregarding words such as: an, a, the.

  3. III.

    Do not use a full stop at the end of each reference.

  4. IV.

    The name of the first listed author or a source is inverted so that the surname appears first. When a source has many authors, only the first listed author’s name is inverted.

  5. V.

    Arrange sources with no author alphabetically by title.Footnote 28

Example: Article in Print Journal

Last name, First initial. “Article Title,” Journal name, Volume. Issue (Year): Page/s.

Jenkins, Oliver. “Unusual Recipes and Cantonese Cuisine,” Culinary Research, Volume 5.8 (1996): pp. 47–59.Footnote 29

Example- Internet database/webpage

Snow, Dan. How did so many solider survive the trenches? (n.d.), http://www.bbc.co.uk/guides/z3kgxs [accessed 18 July 2015]

10. Institute for Electrical and Electronics Engineers (IEEE) style: IEEE is a professional organization that supports many branches of engineering, computer science and information technology. In addition to publishing journals, magazines and conference proceedings, IEEE also sets several standards for a wide variety of industries. The IEEE citation style includes textual text citations counted in square brackets, which refer to the full citation listed in the reference list at the end of the paper. The reference list is organized numerically, not alphabetically.Footnote 30,Footnote 31

Example: Article in Print Journal

Author(s). “Article title”. Journal title, vol., pp, date.

G. Pevere. “Infrared Nation.” The International Journal of Infrared Design, vol. 33, pp. 56–99, Jan. 1979.Footnote 32

Example: Internet database/webpage

A. Altun, “Understanding hypertext in the context of reading on the web: Language learners’ experience,” Current Issues in Education, vol. 6, no. 12, July 2003. [Online]. Available: http://cie.ed.asu.edu/volume6/number12/. [Accessed Dec. 2, 2004].

11. Turabian style: Turabian style was developed by Kate Turabian and elaborated in “A Manual for Writers of Term Papers, Theses, and Dissertations” that is based on the Chicago style. It is specially designed for students writing research papers. Turabian style follow a note system and an author-date system in citation. The notation system is used in the humanities (literature, history, and art), while the author-date system is used in the social sciences.

1. Turabian note citation example:(book)

Turabian in-text citations; The book uses authors’ success stories from their lived experiences to make the case for a creative revolution in the business world (see footnote 1).

Turabian footnote (first reference to a source): (see footnote 1) Dave Stewart and Mark Simmons, The Business Playground: Where Creativity and Commerce Collide (Berkeley: New Riders Press, 2010), p. 22.

Turabian footnote (subsequent references to a source) (see footnote 1); Stewart and Simmons, The Business Playground: Where Creativity and Commerce Collide, p. 22.

Turabian bibliography entry; Stewart, Dave and Mark Simmons. The Business Playground: Where Creativity and Commerce Collide. Berkeley: New Riders Press, 2010.

2. Turabian author-date citation example (book):

Turabian in-text citation; The book uses success stories from the authors’ own lived experiences to make the case for a creative revolution in the business world (Stewart and Simmons 2010, 22).

Turabian reference list entry; Stewart, Dave and Mark Simmons. 2010. The Business Playground: Where Creativity and Commerce Collide. Berkeley: New Riders Press (see footnote 1).

Example: Internet database/webpage

Smith, John. “Obama inaugurated as President.” CNN.com. http://www.cnn.com/POLITICS/01/21/obama_inaugurated/index.html (accessed February 1, 2009).

12. American Political Science Association (APSA) style: APSA is primarily used in political science, with specific regulations for United States government documents. APSA uses an author-date system (see footnote 1).

Example:

Last Name, First Name. Year. Title. Edition. Editor First Name Editor Last Nameed. City: Publisher. (Book)

Rowling, Joanne K. 1997. Harry Potter and the Philosopher’s Stone. 1st ed. London: Bloomsbury Publishing Inc.

Petit, C., and J.M. Sieffermann. 2007. “Testing Consumer Preferences for Iced-Coffee: Does the Drinking Environment Have Any Influence?” 18(1): 161–7.Footnote 33

Example: Internet database/webpage

Postal Service. 2006. United States Code. Title 39, Sec. 3211. http://www.law.cornell.edu/uscode/html/uscode39/usc_sec_39_00003211—000-.html (November 15, 2006).

13. Oxford Standard for the Citation of Legal Authorities (OSCOLA) Style-: This style used by e many students for referencing authorities, law and other legal content. It is widely used in law schools and by journal and book publishers in the UK and abroad.Footnote 34 OSCOLA is used in law schools. It is the prominant citation style for legal academic writing in English. OSCOLA uses a note system; You include a complete description of the source in the footnote.

Example: Book

I. In-text citation: The present book is a systematic collection of research publications in molecular level of sickle syndrome (see footnote 1).

II. Footnote: (see footnote 1) Sanjay Pandey and Sweta Pandey, Updates in Hemoglobinopathies,Thalassemia and IDA Research (Scholars Press, 2019).

III. Reference list entry: Pandey S and Pandey S, Updates in Hemoglobinopathies, Thalassemia and IDA Research (Scholars Press, 2019).

Example: Internet database/webpage

Websites and blogs Sarah Cole, ‘Virtual Friend Fires Employee’ (Naked Law, 1 May 2009) <www.nakedlaw.com/2009/05/index.html> accessed 19 November 2009

14. American Medical Association (AMA) style: The AMA style is often used in medical science and uses a numerical system. Numbering in text is set in superscript, with the page number in parentheses. To create an in text citation in the AMA style, you simply need to include a number in the superscript where the source is relevant. Often a citation is shown with a quote or at the end of a sentence where the source has contributed. The numbered used should be in chronological order from beginning to end of the paper.Footnote 35

Example: Author Last name, First Initial Middle Initial. Title in sentence case. Abbreviated Journal Title in Title Case. Year Month Day; volume (Issue#): PP–PP.

I. In-text citation: This book explores the molecular genetics level research of sickle syndrome, thalassemia and iron deficiency anemia (see footnote 1, p. 3).

II. Reference list entry: Pandey S, Pandey S. Molecular Aspects of Sickle, Thalassemia and Iron Deficiency Anemia. Latvia, EU: Schloars’ Press; 2019

Example: Internet database/webpage

Antimicrobial Resistance. Infectious Diseases Society of America. http://www.idsociety.org/Topic_Antimicrobial_Resistance/. Accessed July 21, 2014.

15. American Chemical Society(ACS) style:

ACS is mainly used in chemistry papers. There are three variations in the ACS style for in-text citations. The choice of style depends on the journal. American Chemical Society developed the ACS style that is used for academic writing in chemistry. ACS uses both numbered and author-date systems.Footnote 36

In-text citation: References in the text must be cited in one of two ways; Depending on the number, either italic numbers in parentheses, or superscript numbers numbered sequentially. If a reference is quoted more than once, it does not receive a new number. When referring to more than one reference at a time, include the reference number in ascending order separated by commas.

By author-date: surname and year of publication in brackets.

Reference list: If the number is quoted by the author, the list of references appears at the end of the paper in the authors’ list, or in alphabetical order if cited by author-date. Use full stops and spaces between beginners. Last name comes first

Example: Book

I. ACS in-text citation (numeric): The present book is systematic collection of research publications in molecular level of sickle syndrome (see footnote 1).

II. ACS in-text citation (author-date): The present book is systematic collection of research publications in molecular level of sickle syndrome. (Pandey and Pandey, 2019).

III. ACS reference list entry: In the reference list, the source is listed alphabetically when the author-date system is used, and by number when a numerical system is used.

Pandey, S.; Pandey, S. Updates in Hemoglobinopathies, Thalassemia and IDA Research; Scholars Press: Latvia, 2019

Example: Internet database/webpage

Matlack, A. S. Introduction to Green Chemistry [Online]; Dekker: New York, 2001. http://web.a.ebscohost.com.libproxy.murdoch.edu.au/ehost/detail/detail?vid=0&sid=a9c47449-b100-446f-b65b-c7143be5caf7%40sessionmgr4009&bdata=JnNpdGU9ZWhvc3QtbGl2ZQ%3d%3d#AN=68196&db=nlebk6 (accessed Apr 24, 2008)

16. National Library of Medicine (NLM) style: NLM writing style guide is used often in medicine and kinesiology. It is written by the International Committee of Medical Journal Editors (ICMJE). NLM is used primarily in the medical world. NLM uses a numeric system.Footnote 37

Example: book

I. NLM in-text citation: Present study reflects the phenotypic and genotypic variability of sickle cell disease [1].

II. NLM reference list entry: 1. Pandey S. Role of the Modulating Fctors on the Phenotype of Sickle Cell Disease. Raleigh: Lulu Publication; 2019.

Example: Internet database/webpage

Animal welfare Information Center [Internet]. Beltsville (MD): National Agricultural Library; [updated 2005 May 4; cited 2006 Feb 17]. Available from: http://nal.usda.gov.awic

17. American Anthropological Association (AAA) style: The AAA documentation style is a close cousin of the Chicago Manual of Style (CMS). The AAA Style Manual, an online publication, provides anthropological writers and scholarly guidelines on AAA variations from CMS style. AAA is based on Chicago style and is primarily used in social studies. AAA style uses an author-date system.Footnote 38

Example: (book)

I. AAA in-text citation: The present book is a systematic collection of research publications in molecular level of sickle syndrome. (Pandey and Pandey, 2019, 10)

II. AAA reference list entry: Pandey Sanjay, and Sweta Pandey 2019 Updates in Hemoglobinopathies, Thalassemia and IDA Research. Latvia: Scholars Press.

Example: Internet database/webpage

Society for Historical Archaeology 2011 What is Historical Archaeology? http://www.sha.org/ accessed October 11, 2013.

Conclusion

Citation and referencing style is an important part of any publication. When a research publication is written and sent for publication in any journal, the reference style of that journal is followed. The journals follow any of the reference styles mentioned above, which are important for early career researchers to know. The early career researchers have a lot of difficulties in finding different reference styles guideline. Through this article, various reference styles have been explained in a very easy way. This article will help the early career researchers to include reference style in their publication in a simple way. Researchers will have easier and better understanding and use of all reference styles on single platform (Table 1).

Table 1 Summary of recommended citing style for various disciplines
Full size table