1 has different meanings.
Citation: quoting allusions; Use allusions. In other words, it is a rhetorical device. Quoting stories or words from ancient books is a classic. You can express relevant content and ideas in a rich and implicit way.
Quote: Based on what others have said (including written materials) or done. Quotes can borrow the original words and become their own language.
2. The emphasis is different.
Allusion: Allusion is to explain the meaning to be expressed in a few sentences, and point out a story in a few sentences. Words and expressions are flexible.
Quote: Quote is to copy the original words and then say what you mean. But sometimes quoting the original words is more authoritative and accurate.
3. The source is different.
Quote: Hong Shen's Preliminary Understanding of Drama Directors: "As for taking association as the main means, there are no allusions in American literature."
Quote: "The Book of the Later Han Dynasty Li Yingchuan": "Therefore, I quote celebrities all over the world."