Today marks 50 years since the landmark papers describing the molecular structure of DNA were published. Due to the X-ray crystallography work of Rosalind Franklin, Watson and Crick were able to deduce the double helix structure of DNA.
You can read the three papers online for free here:
Watson, James Dewey; Crick, Francis Harry Compton (1953-04-25). "Molecular structure of nucleic acids; a structure for deoxyribose nucleic acid". Nature 171 (4356): 737–738. Read here: http://bit.ly/13asBk
Franklin, Rosalind Elsie; Gosling, Raymond (1953-04-25). "Molecular configuration in sodium thymonucleate". Nature 171 (4356): 740–741. Read it here: http://bit.ly/hf4eaz
Wilkins, Maurice Hugh Frederick; Stokes, Alexander Rawson; Wilson, Herbert R. (1953-04-25). "Molecular structure of deoxypentose nucleic acids". Nature 171 (4356): 738–740. Read it here: http://bit.ly/17WK6dI
Happy DNA day!