bluebird .mapSeries() node issue

b3.js

#!/usr/bin/env node

'use strict';

var Promise = require('bluebird');

console.error(Promise.prototype.mapSeries);

function delayResolve(t) {
  return new Promise(function(resolve, reject) {
    setTimeout(function() { resolve(t); }, t); }); }

function delayReject(t) {
  return new Promise(function(resolve, reject) {
    setTimeout(function() { reject(t); }, t); }); }

// .mapSeries() throws error...

//  [email protected] and [email protected]

var p0 = Promise.resolve(delayResolve(200)); // or p0 = delayResolve(200);

p0.then(function() {
  var p1 = delayResolve(500);
  var p2 = delayReject(300);
  var p3 = delayResolve(400);
  // resolved on settleAll (http://bluebirdjs.com/docs/api/reflect.html)
  return Promise.all([p1,p2,p3].map(function(p) {
    return p.reflect(); }));
})
.mapSeries(function(p) {
  return p.isFulfilled() ? p.value() : null;
})
.then(function(r) {
  console.log(JSON.stringify(r));
});

/*
/.../b3.js:30
.mapSeries(function(p) {
 ^

TypeError: p0.then(...).mapSeries is not a function
    at Object.<anonymous> (/.../b3.js:30:2)
    at Module._compile (module.js:410:26)
    at Object.Module._extensions..js (module.js:417:10)
    at Module.load (module.js:344:32)
    at Function.Module._load (module.js:301:12)
    at Function.Module.runMain (module.js:442:10)
    at startup (node.js:136:18)
    at node.js:966:3
*/