1.
Introduction to Logic and to the Methodology of the Deductive Sciences
by Tarski, Alfred, Helmer, Olaf
ISBN: 9780486284620
List Price: $12.95
2.
Looking Forward: A Guide to Futures Research - Olaf Helmer - Hardcover
by Helmer, Olaf
ISBN: 9780803920170
List Price: $32.50
OUT OF STOCK
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Some Potential Societal Developments : 1970-2000
by DeBrigard, Raul, Helmer, Olaf
ISBN: 9780318144221
List Price: $10.50
OUT OF STOCK
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Looking Forward : A Guide to Futures Research
by Helmer, Olaf
ISBN: 9780835784306
List Price: $116.60