(1980). The new Encyclopaedia Britannica: Knowledge in Depth: In 30 vol (15.). Наука.
Чикаго маягийн жагсаалтThe New Encyclopaedia Britannica: Knowledge in Depth: In 30 Vol. 15. Chigago: Наука, 1980.
MLA ишлэлThe New Encyclopaedia Britannica: Knowledge in Depth: In 30 Vol. 15. Наука, 1980.
Warning: These citations may not always be 100% accurate.