Most likely the 1910 Norwegian Census for Alfredia
Elfrida Constance Andersen? in the 1910 Norway Census Name Elfrida Constance Andersen? Marital Status Ugift (Single) Birth Date 21. feb 1894 (21 Feb 1894) Birth Place Eidanger Apartment Etasje 2 Leilighetsnummer 02 Residence Place Porsgrunn, Telemark, Norge (Norway) Relation to Head Datter (Daughter) Settled or Nomadic B Counting District Roligheden 168a Counting District Number 0002 Enumeration District Number 004 Household Members (Name) Age Relationship Didrik Anton Andersen 46 Husfar (Head) Bethia Andersen 24 Hustru (Wife) Elfrida Constance Andersen? 16 Datter (Daughter) Margit Victoria Andersen? 9 Datter (Daughter) Dagmar Bergethe Andersen? 8 Datter (Daughter)
There is an obit for a "Frieda Johnson" who died 21 Sept 1952 beloved wife of Fred B Johnson published in the Chicago Daily News Tues 23 Sept 1952 page 30. She is survived by son Warrant Officer Harold Johnson USAF at Savannah Georgia, daughter Margaret Troup of Santa Barbara, Calif, and a sister in Norway. Burial at Mount Olive
Name Mary Lorriane Troup Sex Female Mother's Name Johnson Event Type Birth Event Date 06 Dec 1936 Event Place Santa Barbara, California, United States Mary Lorriane Troup's Parents and Siblings Johnson Mother F California Birth Index, 1905-1995," database, FamilySearch (https://familysearch.org/ark:/61903/1:1:V2Q8-D5S :
Divorce is considered a public record, largely to avoid commercial fraud by one partner or another. Some states have database of the records. Newspapers are a good source, first as ads published stating that one or another of the partners is disavowing financial responsibililty of charges by the other partner, lists of divorces and of the various stages of the divorce such as filings, hearings and final decrees.