. http://nobelprize.org/educational_games/medicine/dna_double_helix/readmore.html . Retrieved July 30 2006 .   ^ J.D. Watson and F.H.C. Crick, "Molecular Structure of Nucleic Acids" PDF (359  KiB ) , Nature 171.4356 (1953): 737-38. ^ Peter H. Proctor. " Electronic Conduction in Polymers--Historic Papers ". organicsemiconductors.com . http://www.organicsemiconductors.com/weiss.htm . Retrieved 2007-02-12 .   . ^ J.