Looking for Knezevich George of Austria to New York City

Census 1900 found Ann Knezevich birth Sept. 1854 in Ireland Maiden name: (?)
Lived at: 12 Luquer St., Brooklyn, NY
4 children, only 2 living with her in 1900:
Catherine Knezevich Born 1872 Brooklyn, NY Died 1939 Brooklyn, NY (my grandmother)
John Knezevich Born 1878 Brooklyn, NY Died 1912 Brooklyn, NY (Married Mary Lynch)

Ann Knezevich was listed as a widow in the 1900 census.

George KNEZEVICH was said to have been a professor in a University in Austria which would probably have been around 1860s or early 1870s.