What standard should I use for the naming of my MVC controller services?

I have the following:

public class ContentsController : BaseController {
        private IContentService _content;
        private IPageService pageService;
        private IReferenceService _reference;
        private ISequenceService seqService;

        public ContentsController(
            IContentService contentService,
            IPageService pageService,
            IReferenceService referenceService,
            ISequenceService sequenceService) {
            this._content = contentService;
            this.pageService = pageService;
            this._reference = referenceService;
            this.seqService = sequenceService;
        }

Note that it's completely mixed up with different naming standards.

Is there anything recommended for the naming of services that are used by my controller?

I don't think it matters as long as you are consistent. I personally prefer: _{servicename}Service format. ex. _referenceService

public class ContentsController : BaseController {
        private IContentService _contentService;
        private IPageService _pageService;
        private IReferenceService _referenceService;
        private ISequenceService _seqService;

        public ContentsController(
            IContentService contentService,
            IPageService pageService,
            IReferenceService referenceService,
            ISequenceService sequenceService) {
            this._contentService = contentService;
            this._pageService = pageService;
            this._referenceService = referenceService;
            this._seqService = sequenceService;
        }

StackExchange Code Review Q#15614, answer score: 5