Importance of Documenting Sources when Writing Discussion

In a paragraph of no less than 150 words, state your opinion on the importance of documenting sources when writing.

1. Is it important to acknowledge the source(s) of information you have used in your writing? 
2. State why you think it is important or why not.
3. State at least three reasons.
4. Below the paragraph, include three of the sources you have used in your papers; they must be just as you cited them and correctly formatted as per the MLA or APA styles.