?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adissertation&rft.aulast=Ait-Khaled&rft.aufirst=Mounir&rft.au=Ait-Khaled%2C+Mounir&rft.title=Sequence+analysis+of+human+immunodeficiency+virus+type+1%3A+A+cross-sectional+and+longitudinal+analysis&rft.tpages=275&rft.date=1996&rft.inst=UCL+(University+College+London)&rft.degree=Doctoral