Online retailer Amazon.co.uk is to sponsor the British Library's Online Public Access Catalogue (http://opac97. bl.uk). Simon Murdoch, managing director of the company, said the association would allow the British Library to continue to offer the OPAC service, which provides access to catalogues of the major BL collections, free of charge. Amazon will place a company search facility and promotional banners throughout the site that will give users the option to buy books online.