Spear, R. (1976). Hixan analysis: Catastrophe and its preconditions TD342 2/3&4. Open University Press.
Chicago Style aipamenaSpear, Roger. Hixan Analysis: Catastrophe and Its Preconditions TD342 2/3&4. Open University Press, 1976.
MLA aipamenaSpear, Roger. Hixan Analysis: Catastrophe and Its Preconditions TD342 2/3&4. Open University Press, 1976.
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