Media type: E-Article Title: Classes of order 4 in the strict class group of number fields and remarks on unramified quadratic extensions of unit type Contributor: Dummit, David S. imprint: Springer Science and Business Media LLC, 2019 Published in: Annales mathématiques du Québec Language: English DOI: 10.1007/s40316-019-00112-7 ISSN: 2195-4755; 2195-4763 Keywords: General Mathematics Origination: Footnote: