Ord, J. E. (1972). Elementary school social studies for today's children. Harper & Row.
Citazione stile Chigago Style (17a edizione)Ord, John E. Elementary School Social Studies for Today's Children. New York: Harper & Row, 1972.
Citatione MLA (9a ed.)Ord, John E. Elementary School Social Studies for Today's Children. Harper & Row, 1972.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.