Não informado. (1969). Elements. University of Alberta, Department of Elementary Education.
Citação do estilo Chicago (17ª ed.)Não informado. Elements. Alberta, Canada: University of Alberta, Department of Elementary Education, 1969.
Citação MLA (8ª ed.)Não informado. Elements. University of Alberta, Department of Elementary Education, 1969.
警告：这些引文格式不一定是100％准确.