RxJS #5 - unsubscribing

HTML

<script src="https://npmcdn.com/@reactivex/rxjs@5.0.0-beta.1/dist/global/Rx.umd.js"></script>

JavaScript

var source = Rx.Observable.create(observer =>  {
      console.log("call"); 
      observer.next(5);
}).publishReplay().refCount();
    
    subscription1 = source.subscribe({next: (v) => console.log('observerA: ' + v)});
    subscription1.unsubscribe();
    console.log(""); 
    
    subscription2 = source.subscribe({next: (v) => console.log('observerB: ' + v)});
    subscription2.unsubscribe();
    console.log(""); 
    
    subscription3 = source.subscribe({next: (v) => console.log('observerC: ' + v)});
    subscription3.unsubscribe();
    console.log(""); 
    
    subscription4 = source.subscribe({next: (v) => console.log('observerD: ' + v)});
    subscription4.unsubscribe();