Jacob or Jakob Nielsen may refer to:
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Jacob Nielsen, Count of Halland (died c. 1309), great grandson of Valdemar II of Denmark
* , Norway (1768-1822)
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Jakob Nielsen (mathematician)
Jakob Nielsen (15 October 1890 in Mjels, Als (island), Als – 3 August 1959 in Helsingør) was a Danish mathematician known for his work on automorphisms of surface (mathematics), surfaces. He was born in the village Mjels on the island of Als ...
(1890–1959), Danish mathematician known for work on automorphisms of surfaces
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Jakob Nielsen (usability consultant)
Jakob Nielsen (born 5 October 1957) is a Danish web usability consultant, human–computer interaction researcher, and co-founder of Nielsen Norman Group. He was named the “guru of Web page usability” in 1998 by The New York Times and the ...
(born 1957), Danish web usability consultant
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Jakob Axel Nielsen
Jakob Axel Nielsen (born 12 April 1967 in Hadsund) is a Danish lawyer and politician representing the Conservative People's Party. He has been a member of the ''Folketing'' (Parliament of Denmark) from the 2005 to 2010 and was Minister of Traffi ...
(born 1967), Danish lawyer and politician
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Jakob Nielsen (actor) (1900-1978)
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Jacob Nielsen (cyclist)
Jacob Nielsen Larsen (born 12 January 1978, in Horsens
Horsens () is a city on the east coast of the Jutland region of Denmark. It is the seat of the Horsens municipality. The city's population is 64,418 (1 January 2025) and the municipality's ...
(born 1978), Danish cyclist
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Jakob Ahlmann Nielsen (born 1991), Danish footballer
{{hndis, Nielsen, Jacob