How do I find my work dates for a certain job?

How do I find my work dates for a certain job? It was one year ago and I have it on resume still because it shows I have experience in the field I’m applying to. The thing Is that I do not have any of the paystubs or the W2 form anymore. I either lost them or threw them away by mistake. Also, the manager that I am trying to reach is out of the country. How do I find my start and end dates for this job?? I need this to be accurate for a background check.

usa jobs
usa jobs resume
usa hotel jobs
usajobs
usa jobs federal government
usa job in ksa
usa jobs
usa jobs login
usa jobs gov
usajobs.gov
www.usajobs.gov
usajobs.com
usajobs
usajobs.gov official