Angular 4 production build problem

[vishnuindrabalan]

If I am running angular 4 in production mode, then the library causing this error. I removed notification service and it is working.

xERROR TypeError: ctor is not a constructor
at createClass (core.es5.js:9519)
at createProviderInstance$1 (core.es5.js:9484)
at resolveNgModuleDep (core.es5.js:9469)
at NgModuleRef.webpackJsonp.../../../core/@angular/core.es5.js.NgModuleRef.get (core.es5.js:10555)
at resolveDep (core.es5.js:11058)
at createClass (core.es5.js:10911)
at _createProviderInstance (core.es5.js:10881)
at createProviderInstance (core.es5.js:10715)
at createViewNodes (core.es5.js:12168)
at createRootView (core.es5.js:12073)