RAY, S. (2014). OUR EARTH: A BOOK OF GEOGRAPHY - 4. FRANK EDUCATIONAL AIDS.
Cita Chicago (17th ed.)RAY, SUMITRA. OUR EARTH: A BOOK OF GEOGRAPHY - 4. FRANK EDUCATIONAL AIDS, 2014.
Cita MLA (9th ed.)RAY, SUMITRA. OUR EARTH: A BOOK OF GEOGRAPHY - 4. FRANK EDUCATIONAL AIDS, 2014.
Atenció: Aquestes cites poden no estar 100% correctes.