APA (7th ed.) Citation

Keller, V. (1990). Initial steps 4. IBEP.

Chicago Style (17th ed.) Citation

Keller, Victoria. Initial Steps 4. São Paulo, SP: IBEP, 1990.

MLA (9th ed.) Citation

Keller, Victoria. Initial Steps 4. IBEP, 1990.

Warning: These citations may not always be 100% accurate.