var frontEndApp = angular.module('frontEndApp', []);

frontEndApp.factory('customersRepository', function ($resource) {
    return {
        get: function () {
            return $resource('http://localhost/ServiceHub.Web/api/Customers/').query();
        }
    }
});

 function UserRequestCtrl($scope,  customersRepository) {
     $scope.ShortName;
     $scope.FirstName;
     $scope.LastName;
     $scope.UserEmail;
     $scope.UserOrgRole;
     $scope.UserPhoneNumber;

     $scope.customerInstances = customersRepository.get();

     var list = [];

     $scope.checkit = function () {

         for (var p in $scope.customerInstances) {
             if ($scope.customerInstances[p].checked) {
                 list.push($scope.customerInstances[p].CustomerName);

                 console.log("selected customer:  " + $scope.customerInstances[p].CustomerName);
             }
         } return list;
     }

     $scope.saveUser = function () {

         var UserDetail =
             {
                 shortName: $scope.ShortName,
                 firstName: $scope.FirstName,
                 lastName: $scope.LastName,
                 userEmail: $scope.UserEmail,
                 userOrgRole: $scope.UserOrgRole,
                 userPhoneNumber: $scope.UserPhoneNumber,
                 isAdministrator: $scope.UserCitizenship,
                 customerInstances:
                list.filter(function (itm, i, a) {
                    return i == a.indexOf(itm);
                }).toString(),
             }
         console.log("User Detail:  short name  " + $scope.ShortName + "  first name  " + $scope.FirstName + "   last name" + $scope.LastName + "   email  " +
                    $scope.UserEmail + "   org role  " + $scope.UserOrgRole + "   phone  " + $scope.UserPhoneNumber + "   citizenship  " + $scope.UserCitizenship);
         console.log(list.filter(function (itm, i, a) {
             return i == a.indexOf(itm);
         }).toString());


     }
 };

Error: [$injector:unpr] Unknown provider: customersRepositoryProvider <- customersRepository
http://errors.angularjs.org/1.2.16/$injector/unpr?p0=customersRepositoryProvider%20%3C-%20customersRepository

frontEndApp.controller('UserRequestCtrl', function($scope,  customersRepository) {
...
});