High accuracy AM Broadcast stations (probably GPS referenced)

The links below show some GPS referenced AM stations in my area. I will add to these as I have time. Remember, don't use these stations unless you can hear them in the day time. Even then, at the bottom of the sun spot cycle, and in the winter, you still might hear them on Sky Wave. I can sometimes hear stations 300 miles out (or more), especially the big 50 KW ones, in the day time on Sky Wave.  

Because of the possibility of multiple stations on the same frequency, I made sure I had a voice ID on all of these stations. You should do the same before you use them as a reference.

KARN  920   Little Rock

WWLS 640  Oklahoma City

KLIF 570 Dallas

KNX 1070 Los Angeles 50KW OMNI (info from KJ7E)

WWV-2.5 for reference (sky wave)