Sprenger, J. G., Jugton, J., & McIveer, N. (1975). First certificates themes, book 1: Discoveries and inventions. Heinemann Education.
Chicago-viite (17. p.)Sprenger, Judy Garton, Judy Jugton, ja Nick McIveer. First Certificates Themes, Book 1: Discoveries and Inventions. London: Heinemann Education, 1975.
MLA-viite (9. p.)Sprenger, Judy Garton, et al. First Certificates Themes, Book 1: Discoveries and Inventions. Heinemann Education, 1975.
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