RICHARDS, R. (1991). An Early Start To Technology From Science Roy Richars. Simon and Schuster.
Chicago-viite (17. p.)RICHARDS, Roy. An Early Start To Technology From Science Roy Richars. Simon and Schuster, 1991.
MLA-viite (8. p.)RICHARDS, Roy. An Early Start To Technology From Science Roy Richars. Simon and Schuster, 1991.
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