From Frederic's Passport dated 1920:
Son of Joseph Kammerer born in Switzerland and died in New York City in 1875.
He emigrated to the US with his father as a child, on or about 1822
He residedin the US from 1822-1833 and 1851-1875 at New York City, that he was naturalized as a citizen of the United States.
He resided outside the US at the following places for the following periods:
Baden Germany from 1872-1875. Germany Austria, Switzerland, & England from 1877 to 1886
He served for medical relief work in Germany from Dec 1915 to May 1916.
His permanent residence being at New York City, in the State of New York.
He followed the occupation of Physician.
Frederic married Miss Ida Knapp about 1917
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https://www.familysearch.org/ark:/61903/1:1:M59M-1CG
Name: Frederic Kammerer
Event Type: Census US
Event Date: 1910
Event Place: Manhattan Ward 19, New York, New York, United States
Gender: Male
Age: 59
Marital Status: Married
Race: White
Relationship to Head of Household: Head
Years In Present Marriage: 3
Birth Year (Estimated): 1851
Birthplace: New York
Father's Birthplace: New York
Mother's Birthplace: Germany
Sheet Letter: B
Sheet Number: 1
Household Role Sex Age Birthplace
Frederic Kammerer Head Male 59 New York
Ida Kammerer Wife Female 43 Germany
Gesino Semkin Servant Female 32 Germany
Mary Geary Servant Female 29 Ireland
Hannah Wallace Servant Female 23 Ireland

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https://www.familysearch.org/ark:/61903/1:1:QVR2-LYZ5
Frederic Kammerer
United States Passport Applications, 1795-1925
Name: Frederic Kammerer
Event Type: Passport Application
Event Date: 1922
Event Place: Switzerland
Gender: Male
Birth Date: 04 Feb 1856
Birthplace: New York
Spouse's Name: Ida Kammerer
Spouse's Gender: Female