Dear Ms. Herbold,
Thank you for posting your request on History Hub!
If you know the city and/or state location for where the naturalization occurred, then please search this web page www.archives.gov/research/court-records to identify the NARA facility and Federal court. NARA will have a copy of the original Petition for Naturalization that would have been submitted through a Federal court. We suggest that you review Naturalization Records for additional research tips.
If you have not already done so, we also suggest that you search the US Citizenship and Immigration Services (USCIS) Genealogy Program’s website to locate your parents’ records. USCIS maintains immigration and naturalization related files that its predecessor, Immigration and Naturalization Service (INS) created during the mid-1900s. You can submit an Index Search to determine if any records may exist. Your parents may have a Certificate File (C-File) that will contain their Petition for Naturalization and/or Certificate of Naturalization in it.
In addition. please receive Ancestry for Citizenship & Naturalization. There may be a fee for using Ancestry. Instead, you may view these records online at one NARA's facilities for free via a NARA PC. For the nearest NARA location, please consult our web page at https://www.archives.gov/locations/. Also, some of the images from Ancestry are available for free on Family Search at https://www.familysearch.org/en/.
We hope this is helpful. Best of luck with your family research!
[Some information provided by Elizabeth Burnes, Subject Matter Expert]