Citing sources; avoiding plagiarism
R5-a Use a consistent system for citing sources.
In a research paper, you will be drawing on the work of other writers, and you must document
their contributions by citing your sources. You must include a citation when you quote from a
source, when you summarize or paraphrase a source, and when you borrow facts and ideas
from a source that are not common knowledge. (See also R5-b.)
The various academic disciplines use their own editorial styles for citing sources. Most
English professors prefer the Modern Language Association's system of in-text citations, the
system used in examples throughout sections R5 and R6. Here, very briefly, is how an MLA
in-text citation usually works:
1. The source is introduced by a signal phrase that names its author.
2. The material being cited is followed by a page number in parentheses.
3. At the end of the paper, a list of works cited (arranged alphabetically according to the
authors' last names) gives complete publication information about the source.
As lion authority John Seidensticker remarks, "The boldness displayed by mountain
lions just doesn't square with the shy, retiring behavior familiar to those of us who
have studied these animals" (177).
ENTRY IN THE LIST OF WORKS CITED
Seidensticker, John. "Mountain Lions Don't Stalk People: True or False?" Audubon
Feb. 1992: 113-22.
Handling an MLA citation is not always this simple. For a detailed discussion of possible
variations, see Ml.
If your instructor has asked you to use the American Psychological Association (APA)
style of in-text citation, consult Al. If your instructor prefers Chicago-style footnotes or
endnotes, consult A2. For a list of style manuals used in a variety of disciplines, see A3.
R5-b Avoid plagiarism.
Your research paper is a collaboration between you and your sources. To be fair and ethical,
you must acknowledge your debt to the writers of these sources. If you don't, you are guilty of
plagiarism, a serious academic offense.
Three different acts are considered plagiarism: (1) failing to cite quotations and borrowed
ideas, (2) failing to enclose borrowed language in quotation marks, and (3) failing to put
summaries and paraphrases in your own words.
Citing quotations and borrowed ideas
You must of course document all direct quotations. You must also cite any ideas borrowed
from a source: paraphrases of sentences, summaries of paragraphs or chapters, statistics and
little-known facts, and tables, graphs, or diagrams.
The only exception is common knowledge—information that your readers could find in
any number of general sources because it is commonly known. For example, the current
population of the United States is common knowledge in such fields as sociology and
economics; Freud's theory of the unconscious is common knowledge in the field of
As a rule, when you have seen certain information repeatedly in your reading, you don't
need to cite it. However, when information has appeared in only one or two sources or when
it is controversial, you should cite it. If a topic is new to you and you are not sure what is
considered common knowledge or what is controversial, ask someone with expertise. When
in doubt, cite the source.
Enclosing borrowed language in quotation marks
To indicate that you are using a source's exact phrases or sentences, you must enclose them in
quotation marks unless they have been set off from the text by indenting. (See pp. 89-90.) To
omit the quotation marks is to claim—falsely—that the language is your own. Such an
omission is plagiarism even if you have cited the source.
Early colonists viewed the lion as a threat to livestock, as a competitor for the New
World's abundant game, and most importantly, as the personification of the savage
and godless wilderness they meant to cleanse and civilize.
—Kevin Hansen, Cougar, p. 1
Early colonists took a dim view of the lion. According to Kevin Hansen, they saw it
as a threat to livestock, as a competitor for the New World's abundant game, and most
importantly, as the personification of the savage and godless wilderness they meant to
cleanse and civilize (1).
BORROWED LANGUAGE IN QUOTATION MARKS
Early colonists took a dim view of the lion. According to Kevin Hansen, they saw it
"as a threat to livestock, as a competitor for the New World's abundant game, and
most importantly, as the personification of the savage and godless wilderness they
meant to cleanse and civilize" (1).
Putting summaries and paraphrases in your own words
When you summarize or paraphrase, you must restate the source's meaning using your own
language. (See also R3-c.) In the example at the top of page 85, the paraphrase is
plagiarized—even though the source is cited—because too much of its language is borrowed
from the source. The underlined strings of words have been copied word-for-word (without
quotation marks). In addition, the writer has closely followed the sentence structure of the
original source, merely plugging in some synonyms (children for minors, brutally for
severely, and assault for attack).
The park [Caspers Wilderness Park] was closed to minors in 1992 after the family of a girl
severely mauled there in 1986 won a suit against the county. The award of $2.1 million for the
mountain lion attack on Laura Small, who was 5 at the time, was later reduced to $1.5 million.
—Reyes and Messina, "More Warning Signs," p. Bl
PLAGIARISM: UNACCEPTABLE BORROWING
Reyes and Messina report that Caspers Wilderness Park was closed to children in 1992 after
the family of a girl brutally mauled there in 1986 sued the county. The family was ultimately
awarded $1.5 million for the mountain lion assault on Laura Small, who was 5 at the time
To avoid plagiarizing an author's language, set the source aside, write from memory, and
consult the source later to check for accuracy. This strategy prevents you from being
captivated by the words on the page.
TWO ACCEPTABLE PARAPHRASES
Reyes and Messina report that in 1992 Caspers Wilderness Park was placed off-limits to
minors because of an incident that had occurred there some years earlier. In 1986, a five-year-
old, Laura Small, was mauled by a mountain lion and seriously injured. Her family sued the
county and eventually won a settlement of $1.5 million (Bl).
In 1992, officials banned minors from Caspers Wilderness Park. Reyes and Messina explain
that park officials took this measure after a mountain lion attack on a child led to a lawsuit.
The child, five-year-old Laura Small, had been severely mauled by a lion in 1986, and her
parents sued the county. Eventually they received an award of $1.5 million (Bl).
Integrating information from sources
With practice, you will learn to integrate information from sources (quotations, summaries,
paraphrases, and facts) smoothly into your own text.
R6-a Use signal phrases to introduce quotations; limit your use of quotations.
Using signal phrases
Readers need to move from your own words to the words of a source without feeling a jolt.
Avoid dropping quotations into the text without warning. Instead, provide clear signal
phrases, usually including the author's name, to prepare readers for a quotation.
California law prevents the killing of mountain lions except for specific lions that have been
proved to be a threat to humans or livestock. "Fish and Game is even blocked from keeping
mountain lions from killing the endangered desert bighorn sheep" (Perry B4).
QUOTATION WITH SIGNAL PHRASE
California law prevents the killing of mountain lions except for specific lions that have been
proved to be a threat to humans or livestock. Tony Perry points out that, ironically, "Fish and
Game is even blocked from keeping mountain lions from killing the endangered desert
bighorn sheep" (B4).
To avoid monotony, try to vary both the language and the placement of your signal
phrases. The models in the chart on page 87 suggest a range of possibilities.
When your signal phrase includes a verb, choose one that is appropriate in the context. Is
your source arguing a point, making an observation, reporting a fact, drawing a conclusion,
refuting an argument, or stating a belief? By choosing an appropriate verb, you can make your
source's stance clear. See the chart on page 87 for a list of verbs commonly used in signal
Limiting your use of quotations
Although it is tempting to insert many long quotations in your paper and to use your own
words only for connecting passages, do not quote excessively. It is almost impossible to
integrate numerous long quotations smoothly into your own text.
Varying signal phrases
MODEL SIGNAL PHRASES
In the words of lion researcher Maurice Hornocker, „…”
As Kevin Hansen has noted, „…”
Karen McCall and Jim Dutcher point out that „…”
„…” claims CLAW spokesperson Stephani Cruickshank.
„…” writes Rychnovsky, „…”
California politician Tim Leslie offers an odd argument for this view:
Jerome Robinson answers these objections with the following analysis:
VERBS IN SIGNAL PHRASES
acknowledges comments endorses reasons
adds compares grants refutes
admits confirms illustrates rejects
agrees contends implies reports
argues declares insists responds
asserts denies notes suggests
believes disputes observes thinks
claims emphasizes points out writes
Except for the following legitimate uses of quotations, use your own words to summarize
and paraphrase your sources and to explain your own ideas.
WHEN TO USE QUOTATIONS
—When language is especially vivid or expressive
—When exact wording is needed for technical accuracy
—When it is important to let the debaters of an issue explain their positions in their own
—When the words of an important authority lend weight to an argument
—When the language of a source is the topic of your discussion (as in an analysis or
It is not always necessary to quote full sentences from a source. To reduce your reliance
on the words of others, you can often integrate a phrase from a source into your own sentence
Uncommon as lion sightings may be, they are highly publicized. As George Laycock
points out, a lion sighting in southern California "can push Pope, President, or the Los
Angeles Dodgers off the front page" (88).
In the early 1900s, western author Zane Grey wrote that a Navajo hunting guide refused to
participate in a mountain lion hunt "because that would be tantamount to hunting a deity"
Using the ellipsis mark and brackets
Two useful marks of punctuation, the ellipsis mark and brackets, allow you to keep quoted
material to a minimum and to integrate it smoothly into your text.
THE ELLIPSIS MARK To condense a quoted passage, you can use the ellipsis mark (three
periods, with spaces between) to indicate that you have omitted words. What remains must be
MLA now recommends putting brackets around ellipsis dots. These brackets make clear
that the ellipsis dots do not appear in the original work you are quoting. You may wish to
check with your instructor before following this new MLA guideline. If you are using a
citation style other than MLA (such as APA), do not use brackets around ellipsis dots.
Mountain lions are attracted to areas populated by deer. As Kevin Hansen explains, "Deer
are the lion's primary prey [. . .] and deer must be present in sufficient numbers in the
lion's habitat for the cat to survive" (21).
On the rare occasions when you want to omit one or more full sentences, use a period
before the three ellipsis dots.
Michael Milstein, a former ranger for the National Park Service, reports that the eastern
cougar "is probably already extinct. [...] Though rare reports of sightings still surface, a
recent search by the U.S. Fish and Wildlife Service failed to turn up any sightings" (20).
Ordinarily, do not use an ellipsis mark at the beginning or at the end of a quotation. Your
readers will understand that the quoted material is taken from a longer passage, so such marks
are not necessary. The only exception occurs when words at the end of the final quoted
sentence have been dropped. In such cases, put bracketed ellipsis dots before the closing
quotation mark and parenthetical reference: [...]" (103).
Obviously you should not use an ellipsis mark to distort the meaning of your source.
BRACKETS Brackets (square parentheses) allow you to insert words of your own into
quoted material. You can insert words in brackets to clarify matters or to keep a sentence
grammatical in your context.
According to Tony Perry of the Los Angeles Times, "The mountain lion [in California]
has never been in danger of extinction, not even during the 56 years (1907-1963) when
several rural counties in California tried to eradicate lions by paying bounties to hunters"
The writer has added "in California" in brackets to make the context of Perry's claim clear:
Perry is writing about California lions, not about lions in states (such as Florida) where the
lion has faced extinction.
Setting off long quotations
When you quote more than four typed lines of prose or more than three lines of poetry, set off
the quotation by indenting it one inch (or ten spaces) from the left margin. Use the normal
right margin and do not single-space.
Long quotations should be introduced by an informative sentence, usually followed by a
colon. Quotation marks are unnecessary because the indented format tells readers that the
words are taken directly from the source.
Lion researcher Maurice Hornocker offers some practical advice to hikers:
Visitors to lion habitat should carry a big stick and make noise as they hike to let
the animal know they are approaching. Lions are intimidated by height, so if a
cougar is sighted in the area, parents should put their children on their shoulders. If
attacked, a person should not run, nor should he play dead. Stand firm, fight back,
and yell--most people who have resisted attack have successfully fought off the
Notice that at the end of an indented quotation the parenthetical citation goes outside the final
period. (When a quotation runs in to your text, the opposite is true. See the sample citation on
R6-b Use signal phrases to introduce most summaries and paraphrases.
Introduce most summaries and paraphrases with a signal phrase that names the author and
places the material in context. Readers will then understand that everything between the
signal phrase and the parenthetical citation summarizes or paraphrases the cited source.
Without the signal phrase (underlined) in the following example, readers might think that
only the last sentence is being cited, when in fact most of the paragraph is based on the
For much of this century, the U.S. government has encouraged the extermination of
mountain lions and other wild animals. Sketching a brief history, Kevin Hansen tell us
that in 1915 Congress appropriated funds to wipe out animals that were attacking cattle,
and the U.S. Biological Survey hired hunters and trappers to accomplish the mission.
Then, in 1931, the government stepped up its efforts with the passage of the Animal
Damage Control Act, nicknamed "All Dead Critters" by its critics. Between 1937 and
1970, reports Hansen, over seven thousand mountain lions were killed by Animal Damage
Control (57) .
R6-c With statistics and other facts, a signal phrase may not be needed.
When you are citing a statistic or other specific fact, a signal phrase is often not necessary. In
most cases, readers will understand that the citation refers to the statistic or fact (not the whole
Even road kill statistics confirm the dramatic increase in California lions. In the 1970s
only one or two lions were killed on state highways, but twenty-five to thirty were killed
in 1989 alone (Turback 74).
There is nothing wrong, however, with using a signal phrase to introduce a statistic or other
Gary Turback points out that even road kill statistics confirm the dramatic increase in
California lions. In the 1970s, he says, only one or two lions were killed on California
highways, but twenty-five to thirty were killed in 1989 alone (74).
— Is the thesis stated clearly enough? Is it placed where readers will notice it?
— Does each paragraph support the thesis?
— Can readers follow the organization? Would headings help?
— Do topic sentences signal new ideas? Do transitions help readers move from one
major group of paragraphs to another?
— Are ideas presented in a logical order?
— Is the supporting material persuasive? Are the arguments strong enough to stand
up to arguments of those who disagree with the thesis?
— Are the parts proportioned sensibly? Do the major ideas receive enough attention?
— Is the draft concise - free of irrelevant, unimportant, or repetitious material?
— Is the voice appropriate — not top chatty, too stuffy, or too timid?
— Are the sentences clear, emphatic, and varied?
Reviewing a research paper: Use of sources
USE OF QUOTATIONS
— Is quoted material enclosed within quotation marks (unless it has been set off from
the text)? (See R5-b.)
— Is quoted language word-for-word accurate? If not, do brackets indicate the
changes or omissions? (See pp. 88-89)
— Does a clear signal phrase (usually naming the author) prepare readers for each
quotation? (See R6-a.)
— Does a parenthetical citation follow each quotation? (See
USE OF SUMMARIES AND PARAPHRASES
— Are summaries and paraphrases free of plagiarized wording (not copied or half-
copied from the source)? (See R5-b.)
— Are summaries and paraphrases documented with parenthetical citations? (See R5-
— Do readers know where the material being cited begins? In other words, does a
signal phrase mark the beginning of the cited material unless the context makes
clear exactly what is being cited? (See R6-b.)
USE OF STATISTICS AND OTHER FACTS
— Are statistics and facts (other than common knowledge) documented with
parenthetical citations? (See R5-a.)
— If there is no signal phrase, will readers understand exactly which facts are being
cited? (See R6-c)
Revising your draft
When you are revising any paper, it is a good idea to concentrate first on global elements—
focus, organization, content, and audience appeal—and then turn to matters of style and
correctness. (See C4.) With a research paper, this strategy is especially important because
reviewing your use of quotations and other source material requires considerable attention to
On pages 92-93 is a two-part chart for reviewing the draft of a research paper: one part on
global revision, the other on proper handling of sources.
(Source: Hacker, Diana. A Writer’s Reference. Boston/New York: Bedford/St. Martin’s, 2003.)