1. Eberhardt, R., Kubek, M., Unger, H.: Why google isn’t the future. really not. In: Autonomous Systems 2015, pp. 268–281. Mallorca, Spain (2015). Fortschritt-Berichte VDI
2. Brin, S., Page, L.: The anatomy of a large-scale hypertextual web search engine. In: Computer Networks and ISDN Systems of 7th International World Wide Web Conference, pp. 107–117. Brisbane, Australia (1998). Elsevier B.V
3. Search engine market share worldwide. https://gs.statcounter.com/search-engine-market-share. Accessed 8 Apr 2021
4. Yacy search engine software. http://www.yacy.de/de/index.html. Accessed 28 Mar 2021
5. Faroo. http://www.faroo.com/. Accessed 28 Mar 2021