Christophersen, P., & Sandved, A. O. (1977). An advanced english grammar. Macmillan Education.
Chicago Style (17th ed.) ZitazioaChristophersen, Paul, eta Arthur O. Sandved. An Advanced English Grammar. Londres: Macmillan Education, 1977.
MLA (9th ed.) ZitazioaChristophersen, Paul, eta Arthur O. Sandved. An Advanced English Grammar. Macmillan Education, 1977.
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