National Film Board of Canada. (1969). Overhead projectuals catalogue 1969. National Film Board of Canada.
芝加哥风格引文National Film Board of Canada. Overhead Projectuals Catalogue 1969. Montreal: National Film Board of Canada, 1969.
MLA引文National Film Board of Canada. Overhead Projectuals Catalogue 1969. National Film Board of Canada, 1969.
警告：这些引文格式不一定是100％准确.