By Livio, Mario
By George Polya
By Abraham Pais
By Karin Erdmann, Thorsten Holm
By Ian M. Chiswell
By David A. Craven
By D.L. Johnson
By Dirk van Dalen
By Ralf Schindler
By W. Frank Moore, Mark Rogers, Sean Sather-Wagstaff
By Charles Seife
By Hilary Putnam
By John Stillwell
By Geoffrey Howson, Christine Keitel, Jeremy Kilpatrick
By Peter J. Eccles (University of Manchester)
By New Scientist
By William Bolton (Formerly Lecturer, Buckingham Chilterns University College, High Wycombe, UK)
By Lakatos/Worrall/Zahar
By Lave
By Benacerraf, Paul
By Sfard, Anna
By Chaitin, Gregory J.
By Burger, Edward B., Starbird, Michael
By Dunham, WILLIAM
By Keedwell, A. D.
By Lamb, J. D.
By Walker, K.
By Russell, Bertrand
By Lloyd, E. Keith