Ultimately, your professor sets the expectations for which sources you can and can't use. Generally, scholarly journal articles and scholarly books are more reliable and authoritative than those written for popular audiences.
| Scholarly | Popular | Trade | |
|---|---|---|---|
| Example |  |
 |
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| Audience | Academic researchers | General audience | Professionals in the business |
| Authors | Unpaid experts and specialists | Paid staff and freelance journalists and writers | Paid staff writers and industry experts |
| Editors | Unpaid editors and peer reviewers | Paid editors | Paid editors |
| Articles | Usually 10-20 pages, sophisticated text with few charts, graphs, or illustrations | Usually 1-3 pages, easy-to-read text with full-color illustrations | Usually 2-4 pages, easy-to-read text with professional jargon and full-color illustrations |
| Citations | Almost always, many | Rarely, few | Sometimes, few |
