Gangstad, J. E. (1980). The Great Pyramid: Signs in the sun : supplement. Di-Tri Books.
芝加哥风格引文Gangstad, John E. The Great Pyramid: Signs in the Sun : Supplement. Madison, Wis.: Di-Tri Books, 1980.
MLA引文Gangstad, John E. The Great Pyramid: Signs in the Sun : Supplement. Di-Tri Books, 1980.
警告：这些引文格式不一定是100％准确.