Perez, E. J. (1970). Conceptual approach in the teaching of social studies in elementary school.
芝加哥风格引文Perez, Efigenia J. Conceptual Approach in the Teaching of Social Studies in Elementary School. 1970.
MLA引文Perez, Efigenia J. Conceptual Approach in the Teaching of Social Studies in Elementary School. 1970.
警告：这些引文格式不一定是100％准确.