The correct form, briefly
Every major style handles this by naming the original and then indicating where you found it, with only the source you actually read appearing in the reference list. The exact wording differs between styles and the principle does not.
What you must never do is cite the original as though you had read it. That is the version of this that causes real problems, because it is a claim about your own work that is not true.
Why it weakens the citation
You are relying on somebody else's account of what the original said, and that account was written by a person with their own argument to make. Summaries drift, conditions fall away, and a finding gets described in the terms the summarising author needed.
So a secondary citation is evidence about the intermediate source rather than about the original, and a reader who knows the field may well know that the original said something slightly different.
When it is genuinely acceptable
When the original is unobtainable. Out of print, in a language you do not read, held in an archive, or simply never digitised. These are real situations and the secondary form exists precisely for them.
It is also reasonable when the original is peripheral to your argument and you are citing it for context rather than support. What matters is that the weight you put on it matches the confidence you can have in it.
When it is not
When the original is ten minutes away through your library, which it usually is. This is the overwhelmingly common case: the paper is available, and the secondary citation exists because nobody went and got it.
That is the situation a marker is reacting to when they flag it, and the fix is to spend the ten minutes.
What you find when you go back
Frequently something different from what you expected. The original often turns out to be narrower, or to have conditions attached, or to say something more interesting than the summary suggested.
It also gives you a better sentence, because you can describe the study rather than repeat somebody's characterisation of it. That difference is visible in the writing.
How to avoid the situation
Chase citations as you read rather than at the end. When a review cites something you want, look it up immediately and add it to your library. Doing that while you are reading costs almost nothing and removes the problem entirely.
Left to the writing stage it becomes a chore competing with a deadline, and the secondary form starts looking like a reasonable shortcut.
A note on quotations specifically
If you are quoting words rather than reporting a finding, going back to the original is close to mandatory. Quotations get truncated and re-punctuated as they pass through intermediaries, and a misquotation attributed to somebody is a more serious matter than a paraphrase.
Where you genuinely cannot obtain the original, quote it as reported and say so explicitly in the sentence rather than only in the citation.
Why quotations especially
Quotation marks make a promise about exactness that a paraphrase does not. A finding described a little loosely is a minor fault. Words attributed to somebody that they did not write is a different category of error entirely, and it is the one that survives into a permanent record.
Quotations also degrade as they pass between sources. They get truncated, re-punctuated, and stripped of the sentence that qualified them, and each of those changes happens invisibly. By the third repetition a carefully hedged statement can read as a flat assertion.
Questions this raises.
Is secondary citation ever wrong?
It is wrong when the original was available and you did not read it, and it becomes a misrepresentation if you cite the original directly without indicating you read it elsewhere. Used honestly and sparingly for genuinely unobtainable sources, it is a normal part of scholarly writing that every style anticipates.
Do both sources go in the reference list?
Only the one you read, in most styles, because the reference list records what you consulted. The original is named in the text and located through the secondary source. Check your own style manual, because the details differ, and this is one of the entries reference managers handle badly.
What if a whole section of my paper is secondary?
That is a signal to stop and get the originals, because a section built entirely on somebody else's reading of the literature is a summary of a summary. It is also the situation most likely to produce claim drift, where a finding has widened through two retellings before it reaches your sentence.
How do I get an old or obscure paper?
Interlibrary loan handles most of it and is usually free to students, though it takes days rather than minutes, which is an argument for chasing citations early. Authors will frequently send a copy if asked directly. Both routes are worth trying before settling for a secondary citation.
Does this apply to textbooks citing studies?
Especially to textbooks, because they are the most common source of this problem. A textbook describing a study is at least one remove and often two, and the description has been shortened to fit a teaching purpose. If a finding from a textbook matters to your argument, go to the study.
Clara Fairbairn
MA, Writing, on the essays and feedback side of the hall. Writes for The Footnote and coaches the students who bring this work to the desk. The rest of the specialists.
Elsewhere in the hall.
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