As long as the author or the text (if there is only one author) is made clear, you're good. I tend to go ahead and add the fuller reference if it's been more than a page or so or a paragraph or two just to be extra clear (it's never wrong to give the full citation).
Generally, if you are using information from one source in the same paragraph, you only need to use an in-text citation in the first sentence-- as long as it is clear to the reader that all of the information in the paragraph is from the same source.
MLA in-text citation style uses the author's last name and the page number from which the quotation or paraphrase is taken, for example: (Smith 163). If the source does not use page numbers, do not include a number in the parenthetical citation: (Smith).
Try to make it clear in each following sentence if it is still coming from the same source, using phrases like "According to", "They also state...", "That article concludes...". If it is clear, you don't need to repeat the in-text citation for those sentences.
Using In-text Citation
APA in-text citation style uses the author's last name and the year of publication, for example: (Field, 2005). For direct quotations, include the page number as well, for example: (Field, 2005, p. 14). For sources such as websites and e-books that have no page numbers, use a paragraph number.
When paraphrasing or summarising using one source over several sentences or even a whole paragraph, cite the source in the first sentence. There is no need to cite the work again in this paragraph provided it is clear that this is the only source being paraphrased.
Try to make it clear in each following sentence if it is still coming from the same source, using phrases like "According to", "They also state...", "That article concludes...". If it is clear, you don't need to repeat the in-text citation for those sentences.
The number of sources you cite in your paper depends on the purpose of your work. For most papers, cite one or two of the most representative sources for each key point. Literature review papers, however, typically include a more exhaustive list of references.
When citing the work of the same author multiple times in one paragraph, you do not need to reference the author at the end of each sentence. That would look clunky and make your writing stilted. Instead, introduce the author with a full in-text citation at the beginning of the paragraph and then, again, at the end.
How many in-text citations should I have? A good rule to follow, is to have about two sources per paragraph. This means that each source will be cited more than once throughout your paper.
It is useful to paraphrase when your reader needs to understand or be exposed to the argument of another author in order to understand your argument. Paraphrasing ALWAYS requires a citation. Even if you are using your own words, the idea still belongs to someone else.
When citing multiple works parenthetically, place the citations in alphabetical order, separating them with semicolons. Arrange two or more works by the same authors by year of publication. Place citations with no date first. Then, order works with dates in chronological order.
Paraphrasing. When you write information or ideas from a source in your own words, cite the source by adding an in-text citation at the end of the paraphrased portion, like this: This is a paraphrase (Smith 8).
You must cite the source every time you incorporate research, words, ideas, data, or information that is not your own (2). While you are synthesizing and often summarizing many pieces of information, you must cite any concept that is not your own.
You must first cite each source in the body of your essay; these citations within the essay are called in-text citations. You MUST cite all quoted, paraphrased, or summarized words, ideas, and facts from sources.
Note: If an article is only one page long, you do not need to provide the page number in the in-text citation. Note: If there is no author listed, the in-text citation would include the first word or words of the title of the article in quotation marks, e.g. ("Talks").
You should provide an in-text citation whenever you quote, paraphrase or summarize research and ideas that are not your own. This may include theories, best practice guidelines, and of course, statistics. You should also cite whenever you present a fact that is not common knowledge.
In academic writing, as well as in other type so writing, a citation is required whenever information from that source is used in any shape or form, whether it is a quote, paraphrased text or something else. So there is no definite number of times it can be cited.
It is best practice when citing the same source throughout a single paragraph to cite it in the first sentence where it is used, and while the source remains clear and unchanged i.e. you don't refer to another source, do not repeat the citation.
Generally speaking, a good number of citations for a paper is considered to be more than 10–20 citations. However, some fields may require more or fewer citations depending on the topic and the journal.
3000 word essay: 20 sources (or more) listed in the reference list. 5000 word essay: 33 sources (or more) listed in the reference list.
When making reference to the same source for a second or further time in your work, there is no need to repeat the reference in full. It is best to use the shortest form of reference that will still allow a reader to find the source.
You could quote a block literally and cite once. You could then use your own words to summarize if you think it needed. This separates your words from the original. For long runs of literal citations you could use indented blocks and block shading/coloring (if allowed) rather than just quote marks.
Use the word "and" between the authors' names within the text and use the ampersand in parentheses. In subsequent citations, only use the first author's last name followed by "et al." in the signal phrase or in parentheses.
For multiple pages, use the abbreviation “pp.” and separate the page range with an en dash (e.g., pp. 34–36). If pages are discontinuous, use a comma between the page numbers (e.g., pp. 67, 72).