Why we use parenthetical / in-text citations
APA requires the use of in-text or parenthetical citations. We use this to help the reader identify which ideas and facts in the paper come from the particular sources in the reference list.
Author date system
APA uses the author-date system, or the last name of the author and the year published, to help identify sources in the reference list. Place these citations after the information, whether in the middle or at the end of a sentence. If the author or the date is already included in the sentence, then exclude it from the parenthetical citation.
When no author or date is mentioned in the sentence:
When the author is mentioned in the sentence:
When both the date and the author are mentioned in the sentence, do not use parenthetical citations:
Citing sources with more than one author
If there are three or less authors in a source, always cite all these authors when referencing their work:
If there four or five authors, first cite all the authors in the parenthetical citation, then for following references, cite the first author followed by “et al.” Include the year if its the first reference to the citation in the paragraph.
If there are six or more authors, cite the first author followed by “et al.” and the year for all citations.
In the instance where two references with more than six authors reduce to the same form (same first authors), cite enough authors as necessary, then followed by “et al.” to distinguish the two references.
Citing group or corporate authors
Cite a group author (corporations, associations, government agencies, and universities) like you would an author in an in-text citation. If you cite the same group author numerous times, you may add an abbreviation in brackets in the first citation, and later reference that group by the abbreviation.
Citing sources with no author
When there is no author, cite the first few words of what appears in the reference list entry (enough to allow the user to identify the source). If citing the title of an article, chapter, or web page place it in double quotes. If citing a periodical, brochure, book, or report, italicize the title.
Citing authors with the same last name
If two references in your paper have different authors with the same last name, include their initials along with their surname in the body of your paper or in the in-text citation.
Citing multiple works in the same parenthetical citation
When citing numerous works by the same author in the same sentence, arranged by the years of publication.
Works by the same author with the same publication date should be distinguished by suffixes.
When citing two authors in the same in-text citation, order them alphabetically by their last name, and separate them by a semicolon.
Citing old and classic works
Write “n.d.” for sources with no date information where the year would normally be cited. Oftentimes old and classic works will not have date information – when the date information is inapplicable, cite the year the source was translated preceded by “trans.” or the year of the version followed by “Version.”
Citing part of a work
Use a page, chapter, or whatever identifier necessary to help the reader locate the specific part of the source. When quoting a source, always provide page numbers.
When citing an electronic source there may not be page numbers, in which case cite by paragraph number. If there are no labeled page or paragraph numbers, cite the section and the number of the paragraph following it.
Citing personal communications
Emails, letters, interviews, memos and the like are personal communications which do not have recoverable data. For this reason, we only cite such items as in-text citations, and not in the reference list. Cite the initials and the last name, the description of the communication, and the date of the interaction.