Both authors (man and wife) hadn't been in Texas while they wrote it.
Ted Weems [vocal by Perry Como]
Gene Autry [exactly where he came from; born in Tioga Springs, Texas]
Tex Ritter [in film of that name]
Bing Crosby [n°3 US; banned by the BBC during factory hours to prevent workers being detracted by its infectious handclapping rhythm; the war effort came first]
Bob Wills [born deep in the heart of Texas]
Evelyn Künneke [as Das gibt es nur in Texas]
Dave Edmunds' Deep In The Heart Of Texas ('82) was written and recorded first by Geraint Watkins ('79) and covered by Tom Principato ('91).