When should I cite?
- respect copyright;
- give credit to the author of the original work;
- add authority to your work;
- easily find sources;
- demonstrate your search skills;
- avoid plagiarism.
- paraphrasing someone else's idea;
- taking a direct quote from a source;
- referencing another person's ideas;
- using data (statistics, graphics, etc.)
- translating a text.
The same rules apply to electronic sources.
It is not necessary to quote a well known fact, that is to say, a fact that is in principle known to all.
Ex.: The stock market crash of 1929.