7550 Cayton St. – Houston TX (architect: Ursula Oberdieck)
From an advertisement for the 1956 Houston Parade of Homes brochure (thanks to GlenbrookValley.com):
The new ‘openness’ in contemporary styling is incorporated in the combined spacious living room, kitchen and family room, which are separated only by a circular bar. The exterior decorative theme, through its cool restful appearance brings the suggestion of a real country atmosphere to a city home. Sea island white Holiday hillstone is used for outer construction with a contrast being given by cornice trim in lyric blue.
From Popular Mechanics, October 1956 (link)