Choroś, KazimierzKowalska, JustynaStatkiewicz, IzydorAbramowicz, WitoldMayr, Heinrich C.2019-08-122019-08-1220062-88579-179-Xhttps://dl.gi.de/handle/20.500.12116/24154The Internet catalogue is a very easy and comfortable way of retrieving adequate literature and a practical technique for distance booking for interesting items in the library. The Main Library and Scientific Information Centre of the Wroc aw University of Technology has used the electronic catalogues since 1978 and since 1995 they have also been available in the Internet network. In this paper the transaction logs containing 623,875 queries collected over 7 years have been analysed, and then the user sessions have been recognized. The article also discusses two main user strategies: expansion strategy and contraction strategy in his behaviour and in the query refinement in the Internet library catalogues.enText/Conference Paper1617-5468