51. Proofs and Refutations: The Logic of Mathematical Discovery
Price: USD 57.97
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Description: ISBN10: 0521290384, ISBN13: 9780521290388, [publisher: Cambridge University Press] Softcover New! This book is in the same immaculate condition as when it was published [Tucson, AZ, U.S.A.] [Publication Year: 1976]  

52. Proofs and Refutations: The Logic of Mathematical Discovery
Price: USD 58.00
Dealer: Biblio, CMSRAREBOOKS
Description: Cambridge University Press, Date: 1976. 1st Edition. . Soft cover. New. STORED NEW PRISTINE CONDITION SANITIZED THEN WRAPPED 1976. Cambridge University Press ISBN 0521290384 9780521290388 [US] 

53. Proofs and Refutations: The Logic of Mathematical Discovery
Price: USD 58.00
Dealer: Abebooks, BooksByLisa
Description: ISBN10: 0521290384, ISBN13: 9780521290388, [publisher: Cambridge University Press] Softcover First Edition STORED NEW PRISTINE CONDITION SANITIZED THEN WRAPPED [Highland Park, IL, U.S.A.] [Publication Year: 1976]  

54. Proofs and Refutations: The Logic of Mathematical Discovery
Price: USD 59.99
Dealer: Abebooks, GF Books, Inc.
Description: ISBN10: 0521290384, ISBN13: 9780521290388, [publisher: Cambridge University Press] Softcover Book is in NEW condition. [Hawthorne, CA, U.S.A.] [Publication Year: 1976]  

55. Proofs and Refutations: the Logic of Mathematical Discovery
by Lakatos, Imre [Editor]; Worrall, John [Editor]; Zahar, Elie [Editor]; 
Price: USD 64.50
Dealer: Alibris, GridFreed via Alibris
Description: Cambridge University Press 1976-01-01 Paperback New Size: 88x6x136; New. In shrink wrap. Looks like an interesting title! 

56. PROOFS AND REFUTATIONS: THE LOGI
Price: USD 64.50
Dealer: Abebooks, BennettBooksLtd
Description: ISBN10: 0521290384, ISBN13: 9780521290388, [publisher: Cambridge University Press] Softcover New. In shrink wrap. Looks like an interesting title! 0.57 [North Las Vegas, NV, U.S.A.] [Publication Year: 1976]  

57. Proofs and Refutations: The Logic of Mathematical Discovery
by Lakatos Imre Editor; Worrall John Editor; Zahar Elie Editor; 
Price: USD 67.73
Dealer: Biblio, GridFreed LLC
Description: Cambridge University Press, Date: 1976-01-01. Paperback. New. New. In shrink wrap. Looks like an interesting title! 1976. Cambridge University Press ISBN 0521290384 9780521290388 [US] 

58. Proofs and Refutations: The Logic of Mathematical Discovery
by Lakatos, Imre (Editor), and Worrall, John (Editor), and Zahar, Elie (Editor) 
Price: USD 77.28
Dealer: Alibris, Pieuler LLC via Alibris
Description: Cambridge Cambridge University Press 1976 Trade paperback New. Trade paperback (US). Glued binding. 188 p. Contains: Unspecified, Illustrations, black & white. 

59. Proofs And Refutations Pb
by Vv.Aa. 
Price: USD 527.53
Dealer: Abebooks, Iridium_Books
Description: ISBN10: 0521290384, ISBN13: 9780521290388, [publisher: CAMBRIDGE] Softcover [DH, SE, Spain] [Publication Year: 1976]  

60. Proofs and Refutations: the Logic of Mathematical Discovery
by Lakatos Imre; Worrall John L. & Zahar Elie editors 
Price: USD 1470.00
Dealer: Biblio, AB Books
Description: Cambridge University Press. As New. Date: 1977. Hardcover. 0521290384 .*** FREE UPGRADE to Courier/Priority Shipping Upon Request *** - *** IN STOCK AND IMMEDIATELY AVAILABLE FOR SHIPMENT - Text pristine, pages tight to spine - 174 pages. -- with a bonus offer-- . 1977. Cambridge University Press ISBN 0521290384 9780521290388 [US]