Schiffrin, R. S. (1970). English in action: A course for spanish speaking commercial students. Longman.
Čikaški stil citiranja (17. izdanje)Schiffrin, R. S. English in Action: A Course for Spanish Speaking Commercial Students. Gran Bretaña: Longman, 1970.
MLA način citiranja (9. izdanje)Schiffrin, R. S. English in Action: A Course for Spanish Speaking Commercial Students. Longman, 1970.
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