Ninteen Supermodels: Here is a large scan of the 1968 Glamour magazine article.
These 19 models are not the only ones who were considered supermodels at the time but it is a good representation.
BELOW CHERYL TIEGS, LISA PALMER, VERUSCHKA
TWIGGY, SUNNY HARNETT, SUE MURRAY
MARISABERENSON, HEIDEWIEDECK, IRIS BIANCHI, GRETCHENHARRIS
JEAN SHRIMPTON, KATHY CARPENTER, JEAN PATCHETT
PICTURES OF THE NINETEEN SUPERMODELS