I would definitely contact your referees to let them know. Hopefully you'll get the job you want but, no harm in having all of your ducks lined up anyway.
I did once end up in the embarrassing position of having my referee contact me about what they'd said before I'd had a chance to let them know I'd used their name IYSWIM, fortunately they were flattered but better safe than sorry.
Best of luck with the application and (hopefully) resulting interview.
I am applying for jobs at the moment - not even one response yet but I'm applying for one now that I really really want - thing is it is an application form (rather than a cv) and they've asked me to list two referees. I have been self-employed (own business) combined with being a sahm for the past 10 years so have to think really hard about who to nominate. I did ask one person a year ago (but nothing came of that job) so I thought I'd put her name down again and then ask another person - who happens to be on holiday at the moment but I think she's be a good choice. However I have to send the application off now - w'out knowing whether these people will agree to give me a reference (they are people I know - active community members - not friends). The job application says they will not contact them without first telling me so: should I leave asking them to be my referees til I know they might be asked??? I mean, out of 5 job applications I've had one acknowledgement (it's looking like I'm not that desirable an employee) but I've put my all into this job application and would hate to fall when they contact a referee WITHOUT giving me a chance to forewarn them (even though they say they won't). Small dilemma but a dilemma nonetheless!! What should I do???