leadGenSubmit() {

    return this.http.get('http://kmmc.in/wp-content/uploads/2014/01/lesson2.pdf',
    {responseType:ResponseContentType.Blob}).subscribe((data)=>{
        console.log(data);
        var blob = new Blob([data], {type: 'application/pdf'});
        console.log(blob);
        saveAs(blob, "testData.pdf");
    },
    err=>{
        console.log(err);
        }
    )
}

ERROR TypeError: req.responseType.toLowerCase is not a function
    at Observable.eval [as _subscribe] (http.js:2187)
    at Observable._trySubscribe (Observable.js:172)