This cabinet card of an attractive, unidentified couple was taken by photographer W. A.Fermann of Stoughton, Wisconsin. I'm assuming this is a wedding photo due to the white corsage/boutonniere the couple are each wearing. The bride's dark colored dress was not unusual as it was practical and could be reused.
The photographer's full name was William A. Fermann, born in Norway in August of 1839. He emmigrated to the United States in 1867, was married in 1870 to Elise (Unknown). In the 1900 Stoughton, Ward 2, Dane County census, he and his wife were living with a son, William Ebert aged 14. The elder William listed his occupation as photographer. I believe Fermann must have had a lengthy and prosperous photography career in Stoughton as I got many hits when I Googled him.
I believe this particular photograph to be dated about 1889 - 1891 due to several factors including the centered monogram at the bottom of the card, the woman's hairstyle and the style of her dress. Check out The Cabinet Card Gallery to see a photograph also taken by Fermann in which the cabinet card is identical to this one. It is also a wedding photograph and the clothing and photo backdrop are quick simiilar.