Defined things, not defined again... HTML5 Canvas

Cannot read property 'b_Title' of undefined ... yet it is indeed defined. 

This is the offending code:

	this.p_Button.addEventListener("click", APDHMIDM.bind(this)); // error-free

		function b_Lang(){
			if( IsRussia == 1){
			this.p_Button.b_Title.text = ru_APDHMIDM;
			}
			else{
			this.p_Button.b_Title.text = en_APDHMIDM;
			}
		}
		
		b_Lang();

I am differentiating between two languages for a button label to display. This is the code I have been using all along with Zero issues:

this.p_Button.addEventListener("click", APDHMIDM.bind(this));
this.p_Button.b_Title.text = en_APDHMIDM;

So, if property 'b_Title' is defined there, why isn't it in a simple else if function? 

Ideas, anyone? Thanks.