If you have major gaps in employment, there are a few ways to make them less noticeable like a change of resume foramt. It is important to be honest about gaps in your resume and not try to cover them up, but to also make them seem productive and intentional. Adding volunteer work or classes in the time you were unemployed is highly valuable and fairly simple to get starter with.
References. It is assumed that you have references if you have previous employment history. It is not at all necessary to include “references available upon request”, adding this is actually a potential deterrent. Potential employers will ask you for your references later on in the interview process if they see fit. Of course, if references are asked for within the application process, provide them - just not on your resume.