The examples I have by Glenn of California from the late 1950s have a foil label that says "Designed by Macdougall and Stewart". Kipp (neck tie) Stewart and Stewart (bow tie) Macdougall also designed together as design partners pieces for Drexel and as mentioned, American Design Foundation Group.
Also when described as designed by Van Kepple Green, they are Hendrik van Kepple and Taylor Green.
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