  // References
  var Observable = Rx.Observable,
    observableProto = Observable.prototype,
    BinaryDisposable = Rx.BinaryDisposable,
    AnonymousObservable = Rx.AnonymousObservable,
    AbstractObserver = Rx.internals.AbstractObserver,
    disposableEmpty = Rx.Disposable.empty,
    helpers = Rx.helpers,
    defaultComparer = helpers.defaultComparer,
    identity = helpers.identity,
    defaultSubComparer = helpers.defaultSubComparer,
    isFunction = helpers.isFunction,
    isPromise = helpers.isPromise,
    isArrayLike = helpers.isArrayLike,
    isIterable = helpers.isIterable,
    inherits = Rx.internals.inherits,
    observableFromPromise = Observable.fromPromise,
    observableFrom = Observable.from,
    bindCallback = Rx.internals.bindCallback,
    EmptyError = Rx.EmptyError,
    ObservableBase = Rx.ObservableBase,
    ArgumentOutOfRangeError = Rx.ArgumentOutOfRangeError;
