Concepts
If you are referring to an idea from another work but NOT directly quoting the material, or making reference to an entire book, article or other work, you only have to make reference to the author and year of publication and not the page number in your in-text reference.
Paraphrasing
If you are paraphrasing an idea from another work, you only have to make reference to the author and year of publication in your in-text reference and may omit the page numbers. APA guidelines, however, do encourage including a page range for a summary or paraphrase when it will help the reader find the information in a longer work. Paraphrasing is best practice for student papers
Examples
According to Jones (1998), APA style is a difficult citation format for first-time learners.
APA style is a difficult citation format for first-time learners (Jones, 1998, p. 199).
If you are directly quoting from a work, you will need to include the author, year of publication, and page number for the reference (preceded by "p." for a single page and “pp.” for a span of multiple pages, with the page numbers separated by an en dash).
According to Jones (1998), "students often had difficulty using APA style, especially when it was their first time" (p. 199). (best practice)
Jones (1998) found "students often had difficulty using APA style" (p. 199); what implications does this have for teachers?
She stated, "Students often had difficulty using APA style" (Jones, 1998, p. 199), but she did not offer an explanation as to why.
When your parenthetical citation includes two or more works, order them the same way they appear in the reference list (viz., alphabetically), separated by a semi-colon.
(Berndt, 2002; Harlow, 1983)
Generally, writers should endeavor to read primary sources (original sources) and cite those rather than secondary sources (works that report on original sources). Sometimes, however, this is impossible. If you use a source that was cited in another source, name the original source in your signal phrase. List the secondary source in your reference list and include the secondary source in the parentheses. If you know the year of the original source, include it in the citation.
Johnson argued that... (as cited in Smith, 2003, p. 102).
(Johnson, 1985, as cited in Smith, 2003, p. 102).
When an electronic source lacks page numbers, you should try to include information that will help readers find the passage being cited. Use the heading or section name, an abbreviated heading or section name, a paragraph number (para. 1), or a combination of these.
According to Smith (1997), ... (Mind Over Matter section, para. 6). Note: Never use the page numbers of webpages you print out; different computers print webpages with different pagination. Do not use Kindle location numbers; instead, use the page number (available in many Kindle books) or the method above.
Author, A. A., Author, B. B., & Author, C. C. (Year). Title of article. Title of Periodical, volume number(issue number), pages. https://doi.org/xx.xxx/yyyy
Scruton, R. (1996). The eclipse of listening. The New Criterion, 15(3), 5–13.
Organization Name. (Year). Title of report. URL.
United States Government Accountability Office. (2019). Performance and accountability report: Fiscal year 2019. https://www.gao.gov/assets/710/702715.pdf
Lastname, F. M. (Year). Title of entry. In F. M. Lastname (ed.), Title of reference work (edition, page numbers). Publisher.
Tatum, S. R. (2009). Spirituality and religion in hip hop literature and culture. In T. L. Stanley, Encyclopedia of hip hop literature (pp. 250-252). Greenwood.