What keystroke(s) on the keyboard equal this character: ¬

The 2 Jan 2010 digest discussed that character but I am unable to  
duplicate it.

It is in many places in the example program at 5.4.3 Examples/Controls/ 
Button Demo
Here is just one use:
wa = _kWindowCloseBoxAttribute¬
	_kWindowCollapseBoxAttribute

I tried to duplicate those 2 lines of code in my own program file but  
it will not work without that special character.

Thanks