APA aipamena

(2000). Percentage of Students Using Drugs During the Previous 30 Days: 1991-98. U.S. Department of Education.

Chicago Style aipamena

Percentage of Students Using Drugs During the Previous 30 Days: 1991-98. U.S. Department of Education, 2000.

MLA aipamena

Percentage of Students Using Drugs During the Previous 30 Days: 1991-98. U.S. Department of Education, 2000.

Kontuz: berrikusi erreferentzia hauek erabili aurretik.