BALASUBRAMANIAN, P. (2013). TRIPS IN TIME A TEXTBOOK FOR ICSE HISTORY AND CIVICS - BOOK 1. CAMBRIDGE UNIVERSITY PRESS.
Chicago-viite (17. p.)BALASUBRAMANIAN, PREMA. TRIPS IN TIME A TEXTBOOK FOR ICSE HISTORY AND CIVICS - BOOK 1. NEW DELHI: CAMBRIDGE UNIVERSITY PRESS, 2013.
MLA-viite (9. p.)BALASUBRAMANIAN, PREMA. TRIPS IN TIME A TEXTBOOK FOR ICSE HISTORY AND CIVICS - BOOK 1. CAMBRIDGE UNIVERSITY PRESS, 2013.
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