Fritsch, E. C. (1955). Science teaching aids for a stronger America. s.n.
芝加哥风格引文Fritsch, Emery C. Science Teaching Aids for a Stronger America. Illinois: s.n, 1955.
MLA引文Fritsch, Emery C. Science Teaching Aids for a Stronger America. s.n, 1955.
警告：这些引文格式不一定是100％准确.