Dudge, R. E., & Kirchwey, C. B. (1913). The teaching of geography in elementary schools. Rand, McNally.
Cita Chicago (17th ed.)Dudge, Richard Elwood, i Clara Barbara Kirchwey. The Teaching of Geography in Elementary Schools. Chicago: Rand, McNally, 1913.
Cita MLA (9th ed.)Dudge, Richard Elwood, i Clara Barbara Kirchwey. The Teaching of Geography in Elementary Schools. Rand, McNally, 1913.
Atenció: Aquestes cites poden no estar 100% correctes.