Uncertainties of predictions from parton distributions I: Experimental errors A.D. Martin, R.G. Roberts, W.J. Stirling and R.S. Thorne Eur. Phys. J. C, 28 4 (2003) 455-473 Published online: 05 May 2003 DOI: 10.1140/epjc/s2003-01196-2