Butterfield,Jeff. (2019). Soft Skills For Everyone (2nd ed.). Cengage Learning India.
Chicago-viite (17. p.)Butterfield,Jeff. Soft Skills For Everyone. 2nd ed. Delhi: Cengage Learning India, 2019.
MLA-viite (9. p.)Butterfield,Jeff. Soft Skills For Everyone. 2nd ed. Cengage Learning India, 2019.
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