How about the FAA Instrument Flying Handbook:
The desired course is selected by rotating the course-indicating arrow in relation to the azimuth card by means of the course select knob. This gives the pilot a pictorial presentation: the fxed aircraft symbol and course deviation bar display the aircraft relative to the selected course, as though the pilot were above the aircraft looking down. The TO/FROM indicator is a triangular pointer. When the indicator points to the head of the course arrow, it shows that the course selected, if properly intercepted and flown, takes the aircraft to the selected facility.
When the indicator points to the tail of the course arrow, it shows that the course selected, if properly intercepted and fown, takes the aircraft directly away from the selected facility. The glide slope deviation pointer indicates the relation of the aircraft to the glide slope.