Young people's science encyclopedia. [electronic resource] / Edited by the staff of National College of Education.. — [Rev. ed.].. — Chicago, : Children's Press, [1963-64, v.1, 1964]. — 20 v. : illus. (part col.), col. maps, ports. 26 cm.
Анотація: Nearly four-thousand alphabetically arranged topics from many areas of the biological and physical sciences. Also includes more than two hundred suggested experiments and projects.