Não informado. (1970). American secondary education. Ohio Association of Secondary School Administrators.
Citação do estilo Chicago (17ª ed.)Não informado. American Secondary Education. Akron, Ohio: Ohio Association of Secondary School Administrators, 1970.
Citação MLA (8ª ed.)Não informado. American Secondary Education. Ohio Association of Secondary School Administrators, 1970.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.