KRISTIANTO, L. (1997). English for special purposes convertational approach Telephone. Visipro.
Chicago Style aipamenaKRISTIANTO, Lanny. English for Special Purposes Convertational Approach Telephone. Jakarta: Visipro, 1997.
MLA aipamenaKRISTIANTO, Lanny. English for Special Purposes Convertational Approach Telephone. Visipro, 1997.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.