Não informado. (1988). 21st. Century science & technology. 21st. Century Science Associates.
Chicagoスタイル(17版)引用形式Não informado. 21st. Century Science & Technology. Washington: 21st. Century Science Associates, 1988.
MLA(8版)引用形式Não informado. 21st. Century Science & Technology. 21st. Century Science Associates, 1988.
警告: この引用は必ずしも正確ではありません.