APA (7th ed.) Citation

(2001). Blue skies student's book: 4. LongmanI.

Chicago Style (17th ed.) Citation

Blue Skies Student's Book: 4. England: LongmanI, 2001.

MLA (9th ed.) Citation

Blue Skies Student's Book: 4. LongmanI, 2001.

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