Thank-you gift for references?

Current advice on giving references a thank-you gift? I have been interviewing for a high-level position recently and my references were great for me. I am wondering what the current advice is on a thank-you gift for them. These people were a mix of previous supervisors and directs. They are spread around the world so not easy to take them for lunch. I would like to get them a nice bottle of wine but don't necessarily know their taste. I was also thinking of a gift card but then do I go general (i.e. Amazon) or specific (i.e. local wine store)? I would like to do this as soon as possible regardless of whether I get/take the job. I have been signalled that an offer is imminent. Thanks for the advice