Gaya APA

[et.al], C, B, K, B. (2008). As Level and A Level Economics . : University Of Cambridge Local Exami Nations Syndiante.

Gaya MLA

[et.al], Colin, Bamford,, Keith, Brunsikill. "As Level and A Level Economics". : University Of Cambridge Local Exami Nations Syndiante, 2008. Text.