Crayton, C. A. (2004). The A+ exams guide: (exam 220-301), (exam 220-302). Charles River Media.
Lua i Stíl Chicago (17ú heag.)Crayton, Christopher A. The A+ Exams Guide: (exam 220-301), (exam 220-302). Hingham, Mass.: Charles River Media, 2004.
Lua MLA (9ú heag.)Crayton, Christopher A. The A+ Exams Guide: (exam 220-301), (exam 220-302). Charles River Media, 2004.
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