Gaya APA
Butt, J, &, B, C. (2004).
A new reference grammar of modern Spanish, 4th ed. .
New York:
New York McGraw-Hill.
Gaya MLA
Butt, John, &, Benjamin,, Carmen.
"A new reference grammar of modern Spanish, 4th ed. ".
New York:
New York McGraw-Hill,
2004.
Buku.