1. Baeza-Yates, R., & Ribeiro-Neto, B. (2011). Modern information retrieval: The concepts and technology behind search. Addison Wesley.
2. Bradley, P. (2017). Expert internet searching (5th ed.). Facet Publishing. https://doi.org/10.29085/9781783302499
3. Dominikowski, T. (2013). Zur Geschichte der Websuchmaschinen in Deutschland. In D. Lewandowski (Ed.), Handbuch Internet-Suchmaschinen 3: Suchmaschinen zwischen Technik und Gesellschaft (pp. 3–34). Akademische Verlagsgesellschaft AKA.
4. European Commission. (2017). Antitrust: Commission fines Google €2.42 billion for abusing dominance as search engine by giving illegal advantage to own comparison shopping service – Factsheet. http://europa.eu/rapid/press-release_MEMO-17-1785_en.htm
5. Finnemann, N. O. (2019). Web Archive. Knowledge Organization, 46(1), 47–70. https://doi.org/10.5771/0943-7444-2019-1-47