Elshafei, A. (1969). Part Period Algorithm. The Institute of National Planning.
芝加哥风格引文Elshafei, Alwalid. Part Period Algorithm. Cairo: The Institute of National Planning, 1969.
MLA引文Elshafei, Alwalid. Part Period Algorithm. The Institute of National Planning, 1969.
警告：这些引文格式不一定是100％准确.