Hill, D. A. (2013). Life: Pre-Intermediate. Teacher's Book (1a. ed.). National Geographic Learning.
Chicago Style (17th ed.) ZitazioaHill, David A. Life: Pre-Intermediate. Teacher's Book. 1a. ed. Hampshire: National Geographic Learning, 2013.
MLA (9th ed.) ZitazioaHill, David A. Life: Pre-Intermediate. Teacher's Book. 1a. ed. National Geographic Learning, 2013.
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